title: NtrBC-dependent expression from the Rhizobium meliloti dctA promoter in Escherichia coli.
abstract: Effects of the two-component sensor-regulator pairs DctBD and NtrBC upon the expression of a dctA::phoA fusion from Rhizobium meliloti were determined under excess and limiting nitrogen concentrations in Escherichia coli. Results indicated that NtrBC affected transcription from the dctA promoter on a number of regulatory levels and under different physiological conditions in the heterologous host. However, NtrBC-dependent cross-talk was not observed in free-living R. meliloti under the conditions tested. Comparisons of the predicted amino acid sequences of DctD and NtrC from various sources indicated a specific region of the NtrC from rhizobia, which may have diverged from a consensus NtrC/DctD sequence to minimise interference between the two component systems, NtrBC and DctBD.
authors.affiliation: Department of Microbiology, University College Cork, Ireland.
authors.forename: D
authors.initials: D
authors.lastname: Allaway
authors.forename: B
authors.initials: B
authors.lastname: Boesten
authors.forename: F
authors.initials: F
authors.lastname: O'Gara
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis*; D005075:Biological Evolution; D002352:Carrier Proteins / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D029382:Dicarboxylic Acid Transporters; D003998:Dicarboxylic Acids / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins; D008969:Molecular Sequence Data; D051922:PII Nitrogen Regulatory Proteins; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011994:Recombinant Proteins / Q000096:biosynthesis; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D016962:Sinorhizobium meliloti / Q000235:genetics* / Q000378:metabolism; D013045:Species Specificity; D013559:Symbiosis / Q000235:genetics; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D029382:Dicarboxylic Acid Transporters; D003998:Dicarboxylic Acids; D029968:Escherichia coli Proteins; D051922:PII Nitrogen Regulatory Proteins; D011994:Recombinant Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C497876:glnG protein, E coli; C083572:ntrB protein, Rhizobium; C073786:dctA protein, Sinorhizobium meliloti; C073788:dctD protein, Rhizobium meliloti