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Arsenic-transforming microbes and their role in biomining processes.

Drewniak L, Sklodowska A - Environ Sci Pollut Res Int (2013)

Bottom Line: It is well known that microorganisms can dissolve different minerals and use them as sources of nutrients and energy.The majority of rock minerals are rich in vital elements (e.g., P, Fe, S, Mg and Mo), but some may also contain toxic metals or metalloids, like arsenic.The toxicity of arsenic is disclosed after the dissolution of the mineral, which raises two important questions: (1) why do microorganisms dissolve arsenic-bearing minerals and release this metal into the environment in a toxic (also for themselves) form, and (2) How do these microorganisms cope with this toxic element?

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland, ldrewniak@biol.uw.edu.pl.

ABSTRACT
It is well known that microorganisms can dissolve different minerals and use them as sources of nutrients and energy. The majority of rock minerals are rich in vital elements (e.g., P, Fe, S, Mg and Mo), but some may also contain toxic metals or metalloids, like arsenic. The toxicity of arsenic is disclosed after the dissolution of the mineral, which raises two important questions: (1) why do microorganisms dissolve arsenic-bearing minerals and release this metal into the environment in a toxic (also for themselves) form, and (2) How do these microorganisms cope with this toxic element? In this review, we summarize current knowledge about arsenic-transforming microbes and their role in biomining processes. Special consideration is given to studies that have increased our understanding of how microbial activities are linked to the biogeochemistry of arsenic, by examining (1) where and in which forms arsenic occurs in the mining environment, (2) microbial activity in the context of arsenic mineral dissolution and the mechanisms of arsenic resistance, (3) the minerals used and technologies applied in the biomining of arsenic, and (4) how microbes can be used to clean up post-mining environments.

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Related in: MedlinePlus

Microbial transformation of arsenic in mining environments
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Fig1: Microbial transformation of arsenic in mining environments

Mentions: Based on current knowledge about mineral–microbe interactions and experimental data relating to microbially mediated dissolution of arsenic-bearing minerals, we propose a conceptual model for microbial transformation of arsenic in mining environments (Fig. 1). Dissolution of primary arsenic minerals is mediated by both chemolithoautotrophs, that use As, Fe or S as an energy source, as well as arsenic-resistant microbes, which produce extracellular metabolites for nutrient uptake. Secondary arsenic minerals, formed by As(III) and/or As(V) adsorption on ferrous oxides, are dissolved by reductive dissolution mediated by dissimilatory arsenate- or iron-reducing bacteria. Soluble arsenite and arsenate are subjected to constant transformation, which is dependent on local microbial communities, structures and environmental conditions. Volatile arsenic compounds, which can be produced from minerals as well as water-soluble salts, also have a microbial origin (Fig. 1).Fig. 1


Arsenic-transforming microbes and their role in biomining processes.

Drewniak L, Sklodowska A - Environ Sci Pollut Res Int (2013)

Microbial transformation of arsenic in mining environments
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3824281&req=5

Fig1: Microbial transformation of arsenic in mining environments
Mentions: Based on current knowledge about mineral–microbe interactions and experimental data relating to microbially mediated dissolution of arsenic-bearing minerals, we propose a conceptual model for microbial transformation of arsenic in mining environments (Fig. 1). Dissolution of primary arsenic minerals is mediated by both chemolithoautotrophs, that use As, Fe or S as an energy source, as well as arsenic-resistant microbes, which produce extracellular metabolites for nutrient uptake. Secondary arsenic minerals, formed by As(III) and/or As(V) adsorption on ferrous oxides, are dissolved by reductive dissolution mediated by dissimilatory arsenate- or iron-reducing bacteria. Soluble arsenite and arsenate are subjected to constant transformation, which is dependent on local microbial communities, structures and environmental conditions. Volatile arsenic compounds, which can be produced from minerals as well as water-soluble salts, also have a microbial origin (Fig. 1).Fig. 1

Bottom Line: It is well known that microorganisms can dissolve different minerals and use them as sources of nutrients and energy.The majority of rock minerals are rich in vital elements (e.g., P, Fe, S, Mg and Mo), but some may also contain toxic metals or metalloids, like arsenic.The toxicity of arsenic is disclosed after the dissolution of the mineral, which raises two important questions: (1) why do microorganisms dissolve arsenic-bearing minerals and release this metal into the environment in a toxic (also for themselves) form, and (2) How do these microorganisms cope with this toxic element?

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096, Warsaw, Poland, ldrewniak@biol.uw.edu.pl.

ABSTRACT
It is well known that microorganisms can dissolve different minerals and use them as sources of nutrients and energy. The majority of rock minerals are rich in vital elements (e.g., P, Fe, S, Mg and Mo), but some may also contain toxic metals or metalloids, like arsenic. The toxicity of arsenic is disclosed after the dissolution of the mineral, which raises two important questions: (1) why do microorganisms dissolve arsenic-bearing minerals and release this metal into the environment in a toxic (also for themselves) form, and (2) How do these microorganisms cope with this toxic element? In this review, we summarize current knowledge about arsenic-transforming microbes and their role in biomining processes. Special consideration is given to studies that have increased our understanding of how microbial activities are linked to the biogeochemistry of arsenic, by examining (1) where and in which forms arsenic occurs in the mining environment, (2) microbial activity in the context of arsenic mineral dissolution and the mechanisms of arsenic resistance, (3) the minerals used and technologies applied in the biomining of arsenic, and (4) how microbes can be used to clean up post-mining environments.

Show MeSH
Related in: MedlinePlus