A tale of two oxidation states: bacterial colonization of arsenic-rich environments.
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.
Muller
Daniel
D
Génétique Moléculaire, Génomique et Microbiologie, UMR7156 CNRS and Université Louis Pasteur, Strasbourg, France.
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
D001151:Arsenic / Q000378:metabolism*; D001419:Bacteria / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004734:Energy Metabolism; D016680:Genome, Bacterial; D008670:Metals / Q000494:pharmacology; D008954:Models, Biological; D010084:Oxidation-Reduction; D010802:Phylogeny
D008670:Metals; D002244:Carbon; D001151:Arsenic