RefDoc
Haut

Faire une nouvelle recherche
Make a new search
Lancer la recherche


Titre du document / Document title

Diversity of chromium-resistant bacteria isolated from soils contaminated with dichromate

Auteur(s) / Author(s)

CAMARGO Flavio A. O. (1) ; OKEKE Benedict C. (2) ; BENTO Fatima M. (1) ; FRANKENBERGER William T. (2) ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

(1) Department of Soil Science, Federal University of Rio Grande do Sul, Porto Alegre, RS 91540-000, BRESIL
(2) Department of Environmental Sciences, University of California, Riverside, CA 92521, ETATS-UNIS

Résumé / Abstract

Intensive industrial applications of hexavalent chromium [Cr(VI)] have caused substantial soil contamination. Chromium-resistant bacteria (CRB) isolated from soils can be used to transform toxic Cr(VI) to less toxic Cr(III) in soils. The objective of this study was to assess the biodiversity of CRB isolated from soils contaminated with potassium dichromate and evaluate the community response to Cr(VI) toxicity. We isolated 16 CRB from soil samples obtained from Brazil and the U.S. and identified them by 165 rRNA gene sequencing. Ten of our isolates were bacterial species that had never been reported as CRB. Most of the isolates from the Brazilian and U.S. soils belonged to the Bacillaceae family and Actinomicetales order, respectively. Simpson's and Shannon-Weaver diversity indices suggested that the diversity of CRB species was greater in the U.S. soil samples. Bacterial growth and Cr(VI) reduction was affected by different Cr(VI) concentrations. The minimal inhibitory concentration of Cr(Vl) that affected the growth of the isolates varied widely, showing different levels of Cr(VI) resistance. The CRB displayed substantial removal of Cr(VI) achieving 100% removal of 7.5 μM of Cr(VI) in 24 h. Results indicate the presence of a diverse array of CRB adapted to Cr(VI) stress in the two soils.

Revue / Journal Title

Applied soil ecology    ISSN  0929-1393 

Source / Source

2005, vol. 29, no2, pp. 193-202 [10 page(s) (article)] (22 ref.)

Langue / Language

Anglais

Editeur / Publisher

Elsevier, Kidlington, ROYAUME-UNI  (1994) (Revue)

Mots-clés anglais / English Keywords

Soils

;

Dichromates

;

Chromium

;

Bacteria

;

Species diversity

;

Soil science

;

Ecology

;

Minimum inhibitory concentration

;

Contamination

;

Soil pollution

;

Sensitivity resistance

;

Mots-clés français / French Keywords

Sol

;

Dichromate

;

Chrome

;

Bactérie

;

Diversité espèces

;

Science du sol

;

Ecologie

;

Concentration minimale inhibitrice

;

Contamination

;

Pollution sol

;

Sensibilité résistance

;

Mots-clés espagnols / Spanish Keywords

Suelo

;

Dicromato

;

Cromo

;

Bacteria

;

Diversidad especies

;

Ciencia del suelo

;

Ecología

;

Concentración mínima inhibidora

;

Contaminación

;

Polución suelo

;

Sensibilidad resistencia

;

Mots-clés d'auteur / Author Keywords

Chromate-resistant bacteria

;

Chromate reduction

;

Diversity indexes

;

Minimal inhibitory concentration

;

Soil contamination

;

Localisation / Location

INIST-CNRS, Cote INIST : 26979, 35400012542099.0090

Nº notice refdoc (ud4) : 16784478



Faire une nouvelle recherche
Make a new search
Lancer la recherche
Bas