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A two-component regulatory system integrates redox state and population density sensing in Pseudomonas putida.

ABSTRACT: A two-component system formed by a sensor histidine kinase and a response regulator has been identified as an element participating in cell density signal transduction in Pseudomonas putida KT2440. It is a homolog of the Pseudomonas aeruginosa RoxS/RoxR system, which in turn belongs to the RegA/RegB family, described in photosynthetic bacteria as a key regulatory element. In KT2440, the two components are encoded by PP_0887 (roxS) and PP_0888 (roxR), which are transcribed in a single unit. Characterization of this two-component system has revealed its implication in redox signaling and cytochrome oxidase activity, as well as in expression of the cell density-dependent gene ddcA, involved in bacterial colonization of plant surfaces. Whole-genome transcriptional analysis has been performed to define the P. putida RoxS/RoxR regulon. It includes genes involved in sugar and amino acid metabolism and the sulfur starvation response and elements of the respiratory chain (a cbb3 cytochrome oxidase, Fe-S clusters, and cytochrome c-related proteins) or genes participating in the maintenance of the redox balance. A putative RoxR recognition element containing a conserved hexamer (TGCCAG) has also been identified in promoters of genes regulated by this two-component system.

SUBMITTER: Fernandez-Pinar R

PROVIDER: S-EPMC2583600 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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A two-component regulatory system integrates redox state and population density sensing in Pseudomonas putida.

Fernández-Piñar Regina R Ramos Juan Luis JL Rodríguez-Herva José Juan JJ Espinosa-Urgel Manuel M

Journal of bacteriology 20080926 23

A two-component system formed by a sensor histidine kinase and a response regulator has been identified as an element participating in cell density signal transduction in Pseudomonas putida KT2440. It is a homolog of the Pseudomonas aeruginosa RoxS/RoxR system, which in turn belongs to the RegA/RegB family, described in photosynthetic bacteria as a key regulatory element. In KT2440, the two components are encoded by PP_0887 (roxS) and PP_0888 (roxR), which are transcribed in a single unit. Chara ...[more]

PMID: 18820016

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Dataset Information

A two-component regulatory system integrates redox state and population density sensing in Pseudomonas putida.

Publications

A two-component regulatory system integrates redox state and population density sensing in Pseudomonas putida.

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