Accumulation of amorphous Cr(III)-Te(IV) nanoparticles on the surface of Shewanella oneidensis MR-1 through reduction of Cr(VI).
Industrial effluents constitute a major source of metal pollution of aquatic bodies. Moreover, due to their environmental persistence, toxic metal pollution is of special concern. Microbial reduction is considered a promising strategy for toxic metal removal among the several methods available for metal remediation. Here, we describe the coremediation of toxic Cr(VI) and Te(IV) by the dissimilatory metal reducing bacterium-Shewanella oneidensis MR-1. In the presence of both Cr(VI) and Te(IV), S. oneidensis MR-1 reduced Cr(VI) to the less toxic Cr(III) form, but not Te(IV) to Te(0). The reduced Cr(III) ions complexed rapidly with Te(IV) ions and were precipitated from the cell cultures. Electron microscopic analyses revealed that the Cr-Te complexed nanoparticles localized on the bacterial outer membranes. K-edge X-ray absorption spectrometric analyses demonstrated that Cr(III) produced by S. oneidensis MR-1 was rapidly complexed with Te(IV) ions, followed by formation of amorphous Cr(III)-Te(IV) nanoparticles on the cell surface. Our results could be applied for the simultaneous sequestration and detoxification of both Cr(VI) and Te(IV) as well as for the preparation of nanomaterials through environmental friendly processes.
School of Environmental Science and Engineering, Gwangju Institute of Science and Technology , Gwangju 500-712, Republic of Korea.
Dong-Hun
DH
Kim
Sunhwa
S
Park
Min-Gyu
MG
Kim
Hor-Gil
HG
Hur
D001673:Biodegradation, Environmental; D002857:Chromium / Q000737:chemistry / Q000378:metabolism*; D053768:Metal Nanoparticles; D008854:Microscopy, Electron; D010084:Oxidation-Reduction; D020592:Shewanella / Q000378:metabolism; D013691:Tellurium / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism; D056928:X-Ray Absorption Spectroscopy
D014874:Water Pollutants, Chemical; D002857:Chromium; C074702:chromium hexavalent ion; D013691:Tellurium