Premium
The toxicity of lead to Desulfovibrio desulfuricans G20 in the presence of goethite and quartz
Author(s) -
Sani Rajesh K.,
Rastogi Gurdeep,
Moberly James G.,
Dohnalkova Alice,
Ginn Timothy R.,
Spycher Nicolas,
Shende Rajesh V.,
Peyton Brent M.
Publication year - 2010
Publication title -
journal of basic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.58
H-Index - 54
eISSN - 1521-4028
pISSN - 0233-111X
DOI - 10.1002/jobm.200900239
Subject(s) - goethite , desulfovibrio , quartz , toxicity , environmental chemistry , chemistry , lead (geology) , microbiology and biotechnology , geology , metallurgy , biology , materials science , organic chemistry , adsorption , geomorphology , sulfate
An aqueous mixture of goethite, quartz, and lead chloride (PbCl 2 ) was treated with the sulfate‐reducing bacterium, Desulfovibrio desulfuricans G20 ( D. desulfuricans G20), in a medium specifically designed to assess metal toxicity. In the presence of 26 μM of soluble Pb, together with the goethite and quartz, D. desulfuricans G20 grew after a lag time of 5 days compared to 2 days in Pb‐, goethite‐, and quartz‐free treatments. In the absence of goethite and quartz, however, with 26 μM soluble Pb, no measurable growth was observed. Results showed that D. desulfuricans G20 first removed Pb from solutions then growth began resulting in black precipitates of Pb and iron sulfides. Transmission electron microscopic analyses of thin sections of D. desulfuricans G20 treated with 10 μM PbCl 2 in goethite‐ and quartz‐free treatment showed the presence of a dense deposit of lead sulfide precipitates both in the periplasm and cytoplasm. However, thin sections of D. desulfuricans G20 treated with goethite, quartz, and PbCl 2 (26 μM soluble Pb) showed the presence of a dense deposit of iron sulfide precipitates both in the periplasm and cytoplasm. Energy‐dispersive X‐ray spectroscopy, selected area electron diffraction patterns, or X‐ray diffraction analyses confirmed the structure of precipitated Pb inside the cell as galena (PbS) in goethite‐ and quartz‐free treatments, and iron sulfides in treatments with goethite, quartz, and PbCl 2 . Overall results suggest that even at the same soluble Pb concentration (26 μM), in the presence of goethite and quartz, apparent Pb toxicity to D. desulfuricans G20 decreased significantly. Further, accumulation of lead/iron sulfides inside D. desulfuricans G20 cells depended on the presence of goethite and quartz. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)