0000000000274050

AUTHOR

Jens Krämer

showing 3 related works from this author

Citrate Sensing by the C 4 -Dicarboxylate/Citrate Sensor Kinase DcuS of Escherichia coli : Binding Site and Conversion of DcuS to a C 4 -Dicarboxylat…

2007

ABSTRACT The histidine protein kinase DcuS of Escherichia coli senses C 4 -dicarboxylates and citrate by a periplasmic domain. The closely related sensor kinase CitA binds citrate, but no C 4 -dicarboxylates, by a homologous periplasmic domain. CitA is known to bind the three carboxylate and the hydroxyl groups of citrate by sites C1, C2, C3, and H. DcuS requires the same sites for C 4 -dicarboxylate sensing, but only C2 and C3 are highly conserved. It is shown here that sensing of citrate by DcuS required the same sites. Binding of citrate to DcuS, therefore, was similar to binding of C 4 -dicarboxylates but different from that of citrate binding in CitA. DcuS could be converted to a C 4 -…

chemistry.chemical_classificationPeriplasmic spacePlasma protein bindingBiologymedicine.disease_causeMicrobiologychemistry.chemical_compoundEnzymechemistryBiochemistrymedicineBinding siteCitric acidMolecular BiologyEscherichia coliPeptide sequenceHistidineJournal of Bacteriology
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In Vitro Analysis of the Two-Component System MtrB-MtrA from Corynebacterium glutamicum▿ †

2007

ABSTRACT The two-component system MtrBA is involved in the osmostress response of Corynebacterium glutamicum . MtrB was reconstituted in a functionally active form in liposomes and showed autophosphorylation and phosphatase activity. In proteoliposomes, MtrB activity was stimulated by monovalent cations used by many osmosensors for the detection of hypertonicity. Although MtrB was activated by monovalent cations, they lead in vitro to a general stabilization of histidine kinases and do not represent the stimulus for MtrB to sense hyperosmotic stress.

PhosphataseCorynebacteriumEnzyme ActivatorsMicrobiologyCorynebacterium glutamicumEnzyme activatorBacterial ProteinsOsmotic PressurePhosphorylationMolecular BiologyHistidinebiologyAutophosphorylationRNA-Binding ProteinsCations Monovalentbiology.organism_classificationAdaptation PhysiologicalTwo-component regulatory systemPhosphoric Monoester HydrolasesCorynebacterium glutamicumBiochemistryLiposomesPhosphorylationATP-Binding Cassette TransportersSignal TransductionTranscription Factors
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Plasticity of the PAS domain and a potential role for signal transduction in the histidine kinase DcuS

2008

The mechanistic understanding of how membrane-embedded sensor kinases recognize signals and regulate kinase activity is currently limited. Here we report structure-function relationships of the multidomain membrane sensor kinase DcuS using solid-state NMR, structural modeling and mutagenesis. Experimental data of an individual cytoplasmic Per-Arnt-Sim (PAS) domain were compared to structural models generated in silico. These studies, together with previous NMR work on the periplasmic PAS domain, enabled structural investigations of a membrane-embedded 40-kDa construct by solid-state NMR, comprising both PAS segments and the membrane domain. Structural alterations are largely limited to prot…

Models MolecularCytoplasmHistidine KinaseMolecular Sequence DataHAMP domainStructural BiologyPAS domainEscherichia coliAmino Acid SequenceKinase activityProtein Structure QuaternaryNuclear Magnetic Resonance BiomolecularMolecular BiologybiologyEscherichia coli ProteinsHistidine kinaseProtein Structure TertiaryCell biologyTransmembrane domainBiochemistryProtein kinase domainCyclic nucleotide-binding domainbiology.proteinGRB2Protein KinasesSignal Transduction
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