Biomineralization of uranium by PhoY phosphatase activity aids cell survival in Caulobacter crescentus.
Appl Environ Microbiol
; 80(16): 4795-804, 2014 Aug.
Article
em En
| MEDLINE
| ID: mdl-24878600
ABSTRACT
Caulobacter crescentus is known to tolerate high levels of uranium [U(VI)], but its detoxification mechanism is poorly understood. Here we show that C. crescentus is able to facilitate U(VI) biomineralization through the formation of U-Pi precipitates via its native alkaline phosphatase activity. The U-Pi precipitates, deposited on the cell surface in the form of meta-autunite structures, have a lower U/Pi ratio than do chemically produced precipitates. The enzyme that is responsible for the phosphatase activity and thus the biomineralization process is identified as PhoY, a periplasmic alkaline phosphatase with broad substrate specificity. Furthermore, PhoY is shown to confer a survival advantage on C. crescentus toward U(VI) under both growth and nongrowth conditions. Results obtained in this study thus highlight U(VI) biomineralization as a resistance mechanism in microbes, which not only improves our understanding of bacterium-mineral interactions but also aids in defining potential ecological niches for metal-resistant bacteria.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Urânio
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Caulobacter crescentus
/
Fosfatase Alcalina
Idioma:
En
Revista:
Appl Environ Microbiol
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Estados Unidos