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Abstract

A sulfate-reducing bacterium, designated as strain R2, was isolated from wastewater of a ball-bearing manufacturing facility in Tomsk, Western Siberia. This isolate was resistant up to 800 mg Cu/l in the growth medium. By comparison, Cu-resistance of reference cultures of sulfate-reducing bacteria ranged from 50 to 75 mg Cu/l. Growth experiments with strain R2 showed that Cu was an essential trace element and, on one hand, enhanced growth at concentrations up to 10 mg/l but, on the other hand, the growth rate decreased and lag-period extended at copper concentrations of >50 mg/l. Phenotypic characteristics and a 1078 bp nucleotide sequence of the 16S rDNA placed strain R2 within the genus Desulfovibrio. Desulfovibrio R2 carried at least one plasmid of approximately of 23.1 kbp. A 636 bp fragment of the pcoR gene of the pco operon that encodes Cu resistance was amplified by PCR from plasmid DNA of strain R2. The pco genes are involved in Cu-resistance in some enteric and aerobic soil bacteria. Desulfovibrio R2 is a prospective strain for bioremediation purposes and for developing a homologous system for transformation of Cu-resistance in sulfate-reducing bacteria.

Effects of Heavy Metal Ions (Fe<sup>3+</sup>, Cu<sup>2+</sup>, Zn<sup>2+</sup> and Cr<sup>3+</sup>) on the Productivity of Biogas and Biomethane Production

“…In this case, part of the hydrogen sulfide reacts with metal ions in the environment with the formation of metal sulfides, so the inhibitory effect on microorganisms is reduced [29]. Desulfovibrio strain R2 is resistant to 800 mg/dm 3 Cu 2+ because it contains the plasmid gene for resistance to Cu 2+ [30]. The content of copper ions in superoxide dismutase (SODM) and hydrogenase in methanogens [31] may also affect the lack of inhibition.…”

Genome sequence of the acid-tolerant Desulfovibrio sp. DV isolated from the sediments of a Pb-Zn mine tailings dam in the Chita region, Russia

“…are prospective for bioremediation purposes due to their relatively fast growth (compared to other SRB), tolerance to oxygen [5] and, of all SRB, the best understood metabolic features and stress response mechanisms [6] . However, the metal-tolerant Desulfovibrio isolates characterized so far do not tolerate low pH values [7] , [8] , [9] . Recently the first acid-tolerant member of Desulfovibrio , Desulfovibrio sp.…”

Characterization of Copper-Resistant Agrobacterium Isolated from Legume Nodule in Mining Tailings

“…It is an essential trace element, which will enhance the growth of microbes at very low concentrations. At high concentrations, however, it will also harm microbes in various aspects (Ledin 2000;Karnachuk et al 2003). Among the methods available to deal with copper contamination, bioremediation is a relatively efficient and low cost way.…”