GolS controls the response to gold by the hierarchical induction of Salmonella-specific genes that include a CBA efflux-coding operon

Salmonella employs a specific set of proteins that allows it to detect the presence of gold salts in the environment and to mount the appropriate resistance response. This includes a P-type ATPase, GolT, and a small cytoplasmic metal-binding protein, GolB. Their expression is controlled by a MerR-li...

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Detalles Bibliográficos
Autores: Pontel, Lucas Blas, Pérez Audero, María Eugenia, Espariz, Martin, Checa, Susana Karina, Soncini, Fernando Carlos
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/118483
Acceso en línea:http://hdl.handle.net/11336/118483
Access Level:acceso abierto
Palabra clave:GOLS
SALMONELLA
CUER
COPPER
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:Salmonella employs a specific set of proteins that allows it to detect the presence of gold salts in the environment and to mount the appropriate resistance response. This includes a P-type ATPase, GolT, and a small cytoplasmic metal-binding protein, GolB. Their expression is controlled by a MerR-like sensor, GolS, which is highly selective for Au ions. Here, we identify a new GolS-controlled operon named gesABC which codes for a CBA efflux system, and establish its role in Au resistance. GesABC can also mediate drug resistance when induced by Au in a GolS-dependent manner, in a strain deleted in the main drug transporter acrAB. The GolS-controlled transcription of gesABC differs from the other GolS-regulated loci. It is activated by gold, but not induced by copper, even in a strain deleted of the main Cu transporter gene copA, which triggers a substantial GolS-dependent induction of golTS and golB. We demonstrate that the Au-dependent induction of gesABC transcription requires higher GolS levels than for the other members of the gol regulon. This correlates with a divergent GolS operator in the gesABC promoter. We propose that the hierarchical induction within the gol regulon allows Salmonella to cope with Au-contaminated environments.