Functional analysis of the heat shock regulator HrcA of Chlamydia trachomatis.
J Bacteriol
; 184(23): 6566-71, 2002 Dec.
Article
em En
| MEDLINE
| ID: mdl-12426345
ABSTRACT
HrcA is a regulator of bacterial heat shock gene expression that binds to a cis-acting DNA element called CIRCE. It has been proposed that HrcA and CIRCE function as a repressor-operator pair. We have purified recombinant HrcA from the pathogenic bacterium Chlamydia trachomatis and have shown that it is a DNA-binding protein that functions as a negative regulator of transcription. HrcA bound specifically to the CIRCE element in a concentration-dependent manner. HrcA repressed the in vitro transcription of a chlamydial heat shock promoter, and this repression was promoter specific. HrcA-mediated repression appears to be dependent on the topological state of the promoter, as repression on a supercoiled promoter template was greater than that on a linearized template. These results provide direct support for the role of HrcA as a transcriptional repressor in bacteria. This is the first report of the in vitro reconstitution of transcriptional regulation in Chlamydia.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Repressoras
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Transcrição Gênica
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Regulação Bacteriana da Expressão Gênica
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Chlamydia trachomatis
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Elementos Facilitadores Genéticos
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Resposta ao Choque Térmico
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Proteínas de Escherichia coli
Idioma:
En
Revista:
J Bacteriol
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
Estados Unidos