Fumarate regulation of gene expression in Escherichia coli by the DcuSR (dcuSR genes) two-component regulatory system.
In Escherichia coli the genes encoding the anaerobic fumarate respiratory system are transcriptionally regulated by C4-dicarboxylates. The regulation is effected by a two-component regulatory system, DcuSR, consisting of a sensory histidine kinase (DcuS) and a response regulator (DcuR). DcuS and DcuR are encoded by the dcuSR genes (previously yjdHG) at 93.7 min on the calculated E. coli map. Inactivation of the dcuR and dcuS genes caused the loss of C4-dicarboxylate-stimulated synthesis of fumarate reductase (frdABCD genes) and of the anaerobic fumarate-succinate antiporter DcuB (dcuB gene). DcuS is predicted to contain a large periplasmic domain as the supposed site for C4-dicarboxylate sensing. Regulation by DcuR and DcuS responded to the presence of the C4-dicarboxylates fumarate, succinate, malate, aspartate, tartrate, and maleate. Since maleate is not taken up by the bacteria under these conditions, the carboxylates presumably act from without. Genes of the aerobic C4-dicarboxylate pathway encoding succinate dehydrogenase (sdhCDAB) and the aerobic succinate carrier (dctA) are only marginally or negatively regulated by the DcuSR system. The CitAB two-component regulatory system, which is highly similar to DcuSR, had no effect on C4-dicarboxylate regulation of any of the genes.
Institut für Mikrobiologie und Weinforschung, Johannes Gutenberg- Universität Mainz, 55099 Mainz, Germany.
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E
Zientz
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Bongaerts
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G
Unden
D017920:Antiporters / Q000096:biosynthesis; D001426:Bacterial Proteins / Q000096:biosynthesis; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D029382:Dicarboxylic Acid Transporters; D003998:Dicarboxylic Acids / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D029968:Escherichia coli Proteins; D005650:Fumarates / Q000494:pharmacology*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D000071677:Histidine Kinase; D008565:Membrane Proteins / Q000096:biosynthesis; D016254:Mutagenesis, Insertional; D011494:Protein Kinases / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics; D013385:Succinate Dehydrogenase / Q000096:biosynthesis; D014157:Transcription Factors
D017920:Antiporters; D001426:Bacterial Proteins; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C115005:DcuR protein, E coli; D029382:Dicarboxylic Acid Transporters; D003998:Dicarboxylic Acids; D029968:Escherichia coli Proteins; D005650:Fumarates; D008565:Membrane Proteins; D014157:Transcription Factors; C086256:dcuB protein, E coli; C032005:fumaric acid; D013385:Succinate Dehydrogenase; D011494:Protein Kinases; D000071677:Histidine Kinase