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A tale of two oxidation states: bacterial colonization of arsenic-rich environments.

ABSTRACT: Microbial biotransformations have a major impact on contamination by toxic elements, which threatens public health in developing and industrial countries. Finding a means of preserving natural environments-including ground and surface waters-from arsenic constitutes a major challenge facing modern society. Although this metalloid is ubiquitous on Earth, thus far no bacterium thriving in arsenic-contaminated environments has been fully characterized. In-depth exploration of the genome of the beta-proteobacterium Herminiimonas arsenicoxydans with regard to physiology, genetics, and proteomics, revealed that it possesses heretofore unsuspected mechanisms for coping with arsenic. Aside from multiple biochemical processes such as arsenic oxidation, reduction, and efflux, H. arsenicoxydans also exhibits positive chemotaxis and motility towards arsenic and metalloid scavenging by exopolysaccharides. These observations demonstrate the existence of a novel strategy to efficiently colonize arsenic-rich environments, which extends beyond oxidoreduction reactions. Such a microbial mechanism of detoxification, which is possibly exploitable for bioremediation applications of contaminated sites, may have played a crucial role in the occupation of ancient ecological niches on earth.

SUBMITTER: Muller D

PROVIDER: S-EPMC1851979 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature

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A tale of two oxidation states: bacterial colonization of arsenic-rich environments.

Muller Daniel D Médigue Claudine C Koechler Sandrine S Barbe Valérie V Barakat Mohamed M Talla Emmanuel E Bonnefoy Violaine V Krin Evelyne E Arsène-Ploetze Florence F Carapito Christine C Chandler Michael M Cournoyer Benoît B Cruveiller Stéphane S Dossat Caroline C Duval Simon S Heymann Michael M Leize Emmanuelle E Lieutaud Aurélie A Lièvremont Didier D Makita Yuko Y Mangenot Sophie S Nitschke Wolfgang W Ortet Philippe P Perdrial Nicolas N Schoepp Barbara B Siguier Patricia P Simeonova Diliana D DD Rouy Zoé Z Segurens Béatrice B Turlin Evelyne E Vallenet David D Van Dorsselaer Alain A Weiss Stéphanie S Weissenbach Jean J Lett Marie-Claire MC Danchin Antoine A Bertin Philippe N PN

PLoS genetics 20070305 4

Microbial biotransformations have a major impact on contamination by toxic elements, which threatens public health in developing and industrial countries. Finding a means of preserving natural environments-including ground and surface waters-from arsenic constitutes a major challenge facing modern society. Although this metalloid is ubiquitous on Earth, thus far no bacterium thriving in arsenic-contaminated environments has been fully characterized. In-depth exploration of the genome of the beta ...[more]

PMID: 17432936

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Dataset Information

A tale of two oxidation states: bacterial colonization of arsenic-rich environments.

Publications

A tale of two oxidation states: bacterial colonization of arsenic-rich environments.

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