0000000000363178

AUTHOR

G. Holighaus

showing 2 related works from this author

O2-sensing and O2-dependent gene regulation in facultatively anaerobic bacteria.

1995

Availability of O2 is one of the most important regulatory signals in facultatively anaerobic bacteria. Various two- or one-component sensor/regulator systems control the expression of aerobic and anaerobic metabolism in response to O2. Most of the sensor proteins contain heme or Fe as cofactors that interact with O2 either by binding or by a redox reaction. The ArcA/ArcB regulator of aerobic metabolism in Escherichia coli may use a different sensory mechanism. In two-component regulators, the sensor is located in the cytoplasmic membrane, whereas one-component regulators are located in the cytoplasm. Under most conditions, O2 can readily reach the cytoplasm and could provide the signal in …

Iron-Sulfur ProteinsGram-Negative Facultatively Anaerobic RodsAnaerobic respirationRegulatorBiologymedicine.disease_causeBiochemistryMicrobiologychemistry.chemical_compoundBacterial ProteinsGeneticsmedicineMolecular BiologyHemeEscherichia coliRegulation of gene expressionSensory mechanismEscherichia coli ProteinsGeneral MedicineGene Expression Regulation Bacterialbiology.organism_classificationOxygenchemistryBiochemistrybacteriaAnaerobic bacteriaBacteriaTranscription FactorsArchives of microbiology
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O2 as the regulatory signal for FNR-dependent gene regulation in Escherichia coli

1996

With an oxystat, changes in the pattern of expression of FNR-dependent genes from Escherichia coli were studied as a function of the O2 tension (pO2) in the medium. Expression of all four tested genes was decreased by increasing O2. However, the pO2 values that gave rise to half-maximal repression (pO(0.5)) were dependent on the particular promoter and varied between 1 and 5 millibars (1 bar = 10(5) Pa). The pO(0.5) value for the ArcA-regulated succinate dehydrogenase genes was in the same range (pO(0.5) = 4.6 millibars). At these pO2 values, the cytoplasm can be calculated to be well supplied with O2 by diffusion. Therefore, intracellular O2 could provide the signal to FNR, suggesting that…

Iron-Sulfur ProteinsCellular respirationRepressorBiologymedicine.disease_causeMicrobiologyElectron TransportBacterial ProteinsGenes RegulatorEscherichia colimedicineAnaerobiosisMolecular BiologyEscherichia coliRegulation of gene expressionchemistry.chemical_classificationEscherichia coli ProteinsSuccinate dehydrogenaseMembrane ProteinsGene Expression Regulation BacterialElectron transport chainAerobiosisOxygenRepressor ProteinsSuccinate DehydrogenaseEnzymeLac OperonchemistryBiochemistryGenes BacterialMutationbiology.proteinOxidation-ReductionProtein KinasesIntracellularBacterial Outer Membrane ProteinsSignal TransductionResearch ArticleJournal of Bacteriology
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