Redox control of copper homeostasis in cyanobacteria.

Copper is essential for all living organisms but is toxic when present in excess. Therefore organisms have developed homeostatic mechanism to tightly regulate its cellular concentration. In a recent study we have shown that CopRS two-component system is essential for copper resistance in the cyanoba...

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Detalhes bibliográficos
Autores: López-Maury, Luis, Giner-Lamia, Joaquín, Florencio, Francisco J.
Tipo de documento: artigo
Data de publicação:2012
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositório:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/98446
Acesso em linha:http://hdl.handle.net/10261/98446
Access Level:Acceso aberto
Palavra-chave:Synechocystis.
Thylakoid
Two-component system
Histidine kinase
Copper
Descrição
Resumo:Copper is essential for all living organisms but is toxic when present in excess. Therefore organisms have developed homeostatic mechanism to tightly regulate its cellular concentration. In a recent study we have shown that CopRS two-component system is essential for copper resistance in the cyanobacterium Synechocystis sp PCC 6803. This two-component regulates expression of a heavy-metal RND type copper efflux system (encoded by copBAC) as well as its own expression (in the copMRS operon) in response to an excess of copper in the media. We have also observed that both operons are induced under condition that reduces the photosynthetic electron flow and this induction depends of the presence of the copper-protein, plastocyanin. These findings, together with CopS localization to the thylakoid membrane and its periplasmic domain being able to bind copper directly, suggest that CopS could be involved in copper detection in both the periplasm and the thylakoid lumen.