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The two-component system PhoPR of Clostridium acetobutylicum is involved in phosphate-dependent gene regulation.

ABSTRACT: The phoPR gene locus of Clostridium acetobutylicum ATCC 824 comprises two genes, phoP and phoR. Deduced proteins are predicted to represent a response regulator and sensor kinase of a phosphate-dependent two-component regulatory system. We analyzed the expression patterns of phoPR in P(i)-limited chemostat cultures and in response to P(i) pulses. A basic transcription level under high-phosphate conditions was shown, and a significant increase in mRNA transcript levels was found when external P(i) concentrations dropped below 0.3 mM. In two-dimensional gel electrophoresis experiments, a 2.5-fold increase in PhoP was observed under P(i)-limiting growth conditions compared to growth with an excess of P(i). At least three different transcription start points for phoP were determined by primer extension analyses. Proteins PhoP and an N-terminally truncated *PhoR were individually expressed heterologously in Escherichia coli and purified. Autophosphorylation of *PhoR and phosphorylation of PhoP were shown in vitro. Electromobility shift assays proved that there was a specific binding of PhoP to the promoter region of the phosphate-regulated pst operon of C. acetobutylicum.

SUBMITTER: Fiedler T

PROVIDER: S-EPMC2566200 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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The two-component system PhoPR of Clostridium acetobutylicum is involved in phosphate-dependent gene regulation.

Fiedler Tomas T Mix Maren M Meyer Uta U Mikkat Stefan S Glocker Michael O MO Bahl Hubert H Fischer Ralf-Jörg RJ

Journal of bacteriology 20080808 20

The phoPR gene locus of Clostridium acetobutylicum ATCC 824 comprises two genes, phoP and phoR. Deduced proteins are predicted to represent a response regulator and sensor kinase of a phosphate-dependent two-component regulatory system. We analyzed the expression patterns of phoPR in P(i)-limited chemostat cultures and in response to P(i) pulses. A basic transcription level under high-phosphate conditions was shown, and a significant increase in mRNA transcript levels was found when external P(i ...[more]

PMID: 18689481

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Dataset Information

The two-component system PhoPR of Clostridium acetobutylicum is involved in phosphate-dependent gene regulation.

Publications

The two-component system PhoPR of Clostridium acetobutylicum is involved in phosphate-dependent gene regulation.

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