Iron regulates expression of Bacillus cereus hemolysin II via global regulator Fur.
J Bacteriol
; 194(13): 3327-35, 2012 Jul.
Article
en En
| MEDLINE
| ID: mdl-22522892
ABSTRACT
The capacity of pathogens to respond to environmental signals, such as iron concentration, is key to bacterial survival and establishment of a successful infection. Bacillus cereus is a widely distributed bacterium with distinct pathogenic properties. Hemolysin II (HlyII) is one of its pore-forming cytotoxins and has been shown to be involved in bacterial pathogenicity in a number of cell and animal models. Unlike many other B. cereus pathogenicity factors, HlyII is not regulated by pleiotropic transcriptional regulator PlcR but is controlled by its own regulator, HlyIIR. Using a combination of in vivo and in vitro techniques, we show that hlyII expression is also negatively regulated by iron by the global regulator Fur via direct interaction with the hlyII promoter. DNase I footprinting and in vitro transcription experiments indicate that Fur prevents RNA polymerase binding to the hlyII promoter. HlyII expression profiles demonstrate that both HlyIIR and Fur regulate HlyII expression in a concerted fashion, with the effect of Fur being maximal in the early stages of bacterial growth. In sum, these results show that Fur serves as a transcriptional repressor for hlyII expression.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas Represoras
/
Bacillus cereus
/
Proteínas Bacterianas
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Regulación Bacteriana de la Expresión Génica
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Proteínas Hemolisinas
/
Hierro
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
J Bacteriol
Año:
2012
Tipo del documento:
Article
País de afiliación:
Rusia