Induced formation of chelating agents byPseudomonas aeruginosa grown in presence of thorium and uranium

Premuzic, E.T.; Lin, Mow S.

doi:10.1007/bf01055783

Cited by 64 publications

(24 citation statements)

References 35 publications

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“…Actinides interact mainly with functional groups on the cell surface [6,7] and with metabolic products released by bacteria. [8] Only in certain cases can actinides penetrate the cell walls and be taken up by the bacteria. [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.…”

Section: Introductionmentioning

confidence: 99%

Laser Spectroscopic Studies of Interactions of U^VI with Bacterial Phosphate Species

Knopp

Panak

Wray

et al. 2003

Chemistry A European J

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We have investigated the interactions of UVI with two bacterial phosphate-containing species: Gram-positive Bacillus sphaericus and Gram-negative Pseudomonas aeruginosa. The Gram-positive B. sphaericus was investigated by using Raman spectroscopy and time-resolved laser-induced fluorescence spectroscopy (TRLFS). We found that living cells, spores, and intact heat-killed cells complexed UVI (pH 4.5) through phosphate groups bound to their surfaces, while decomposed cells released H2PO4- and precipitated UVI as UO2(H2PO4)2. TRLFS of UVI showed that Gram-negative P. aeruginosa--genetically engineered to accumulate polyphosphate, subsequently degrade it, and secrete phosphate--precipitated UVI quantitatively at pH 4.5. The same bacterial strain, not induced to secrete phosphate, sorbed only a small amount of UVI.

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Section: Introductionmentioning

confidence: 99%

Laser Spectroscopic Studies of Interactions of U^VI with Bacterial Phosphate Species

Knopp

Panak

Wray

et al. 2003

Chemistry A European J

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“…4b), in accordance with the cell-surface pattern of uranyl deposition seen previously with Saccharomyces (Strandberg et al, 1981) and Pseudomonas (Strandberg et al, 1981;Marques et al, 1991), where the uptake of uranyl was rapid and largely membrane-localized. To date, there is no evidence from the literature that uranyl ion is able to enter the cytoplasmic compartment of living cells (probably attributable to the large size and stereochemistry of UOt+ and its associated hydroxyl groups; Weigel, 1986), even though uranyl ion induces formation of the chelating agents probably responsible for iron acquisition in Pseudomonas aeruginosa (Premuzic et al, 1985). Strandberg et al (1981) noted that uranyl uptake occurred rapidly in P. aeruginosa, but the mechanism of translocation of UO:+ across the outer membrane and to the cytoplasmic membrane is still unknown.…”

Section: Events During the Initial Stages Of Uranyl Ion Depositionmentioning

confidence: 99%

Localization of enzymically enhanced heavy metal accumulation by Citrobacter sp. and metal accumulation in vitro by liposomes containing entrapped enzyme

et al. 1997

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A heavy-metal-accumulating Citrobacter sp. has been used for the treatment of metal-laden industrial wastes. Metal uptake is mediated via a cell-bound phosphatase that liberates inorganic phosphate which precipitates with heavy metals as cell-bound metal phosphate. A phosphatase-def icient mutant accumulated little UOf+, while a phosphatase-overproducing mutant accumulated correspondingly more metal, with a uranium loading equivalent to the bacterial dry weight achieved after 6 h exposure of resting cells to uranyl ion in the presence of phosphatase substrate (glycerol 2-phosphate). The phosphatase, visualized by immunogold labelling in the parent and overproducing strains, but not seen in the deficient mutant, was held within the periplasmic space with, in some cells, a higher concentration at the polar regions. Enzyme was also associated with the outer membrane and found extracellularly. Accumulated uranyl phosphate was visible as cell-surface-and polar-localized deposits, identified by energy-dispersive X-ray analysis (EDAX), proton-induced X-ray emission analysis (PIXE) and X-ray diffraction analysis (XRD) as polycrystalline HUO,PO,AH,O. Nucleation sites for initiation of biocrystallization were identified at the cytoplasmic and outer membranes, prompting consideration of an in vitro biocatalytic system for metal waste remediation. Phosphatidylcholine-based liposomes with entrapped phosphatase released phosphate comparably to whole cells, as shown by 31P NMR spectroscopy in the presence of NMR-silent ' 'l2Cd2+. Application of liposome-immobilized enzyme to the decontamination of uranyl solutions was, however, limited by rapid fouling of the biocatalyst by deposited uranyl phosphate. It is suggested that the architecture of the bacterial cell surface provides a means of access of uranyl ion to the inner and outer membranes and enzymically liberated phosphate in a way that minimizes fouling in whole cells.

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“…Banaszak et al (1999) (Barnhart et al, 1980). The production of extracellular chelating agents resembling siderophores was observed for Pseudomonas aeruginosa grown in the presence of uranium and thorium (Premuzic et al, 1985). Brainard et al (1992) (Wildung and Garland, 1980;Wildung et al, 1987;Beckert and Au, 1976).…”

Section: Radiation and Heavv Metal Effects (Pu Isotones Effect) It Wmentioning

confidence: 99%

Microbial transformations of plutonium and implications for its mobility

Francis

2001

Radioactivity in the Environment

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Induced formation of chelating agents byPseudomonas aeruginosa grown in presence of thorium and uranium

Cited by 64 publications

References 35 publications

Laser Spectroscopic Studies of Interactions of U^VI with Bacterial Phosphate Species

Laser Spectroscopic Studies of Interactions of U^VI with Bacterial Phosphate Species

Localization of enzymically enhanced heavy metal accumulation by Citrobacter sp. and metal accumulation in vitro by liposomes containing entrapped enzyme

Microbial transformations of plutonium and implications for its mobility

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Induced formation of chelating agents byPseudomonas aeruginosa grown in presence of thorium and uranium

Cited by 64 publications

References 35 publications

Laser Spectroscopic Studies of Interactions of UVI with Bacterial Phosphate Species

Laser Spectroscopic Studies of Interactions of UVI with Bacterial Phosphate Species

Localization of enzymically enhanced heavy metal accumulation by Citrobacter sp. and metal accumulation in vitro by liposomes containing entrapped enzyme

Microbial transformations of plutonium and implications for its mobility

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Laser Spectroscopic Studies of Interactions of U^VI with Bacterial Phosphate Species

Laser Spectroscopic Studies of Interactions of U^VI with Bacterial Phosphate Species