scholarly journals The ArcB Sensor Kinase of Escherichia coli Autophosphorylates by an Intramolecular Reaction

2010 ◽  
Vol 192 (6) ◽  
pp. 1735-1739 ◽  
Author(s):  
Gabriela R. Peña-Sandoval ◽  
Dimitris Georgellis
Keyword(s):  
Response Regulator ◽  
Bond Formation ◽  
Sensor Kinase ◽  
Two Component System ◽  
Histidine Kinases ◽  
Intramolecular Reaction ◽  
Redox Active ◽  
Intermolecular Disulfide Bond ◽  
Two Component ◽  
Respiratory Conditions

ABSTRACT The Arc two-component system, comprising the ArcB sensor kinase and the ArcA response regulator, modulates the expression of numerous genes in response to the respiratory conditions of growth. ArcB is a tripartite histidine kinase whose activity is regulated by the oxidation of two cytosol-located redox-active cysteine residues that participate in intermolecular disulfide bond formation. Here we show that ArcB autophosphorylates through an intramolecular reaction which diverges from the usually envisaged intermolecular autophosphorylation of homodimeric histidine kinases.

scholarly journals Requirement of the Receiver and Phosphotransfer Domains of ArcB for Efficient Dephosphorylation of Phosphorylated ArcA In Vivo

2005 ◽  
Vol 187 (9) ◽  
pp. 3267-3272 ◽  
Author(s):  
Gabriela R. Peña-Sandoval ◽  
Ohsuk Kwon ◽  
Dimitris Georgellis
Keyword(s):  
Response Regulator ◽  
Growth Conditions ◽  
Sensor Kinase ◽  
Aerobic Growth ◽  
Two Component System ◽  
Two Component ◽  
Necessary And Sufficient ◽  
Respiratory Conditions

ABSTRACT The Arc two-component system, comprising the ArcB sensor kinase and the ArcA response regulator, modulates the expression of numerous genes in response to the respiratory conditions of growth. Under anoxic growth conditions, ArcB autophosphorylates and transphosphorylates ArcA, which in turn represses or activates its target operons. Under aerobic growth conditions, phosphorylated ArcA (ArcA-P) dephosphorylates and its transcriptional regulation is released. The dephosphorylation of ArcA-P has been shown to occur, at least in vitro, via an ArcAAsp54-P → ArcBHis717-P → ArcBAsp576-P → Pi reverse phosphorelay. In this study, the physiological significance of this pathway was assessed. The results demonstrate that the receiver and phosphotransfer domains of the tripartite sensor kinase ArcB are necessary and sufficient for efficient ArcA-P dephosphorylation in vivo.

scholarly journals A Novel Three-Protein Two-Component System Provides a Regulatory Twist on an Established Circuit To Modulate Expression of the cbbI Region of Rhodopseudomonas palustris CGA010

2006 ◽  
Vol 188 (8) ◽  
pp. 2780-2791 ◽  
Author(s):  
Simona Romagnoli ◽  
F. Robert Tabita
Keyword(s):  
Response Regulator ◽  
Rhodopseudomonas Palustris ◽  
Sensor Kinase ◽  
Response Regulators ◽  
Transcription Activator ◽  
Two Component System ◽  
Bisphosphate Carboxylase ◽  
Control Of Gene Expression ◽  
Component System ◽  
Two Component

ABSTRACT A novel two-component system has been identified in the cbbI region of the nonsulfur purple photosynthetic bacterium Rhodopseudomonas palustris. Genes encoding this system, here designated cbbRRS, are juxtaposed between the divergently transcribed transcription activator gene, cbbR, and the form I ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) genes, cbbLS. The three genes of the cbbRRS system represent a variation of the well-known two-component signal transduction systems, as there are a transmembrane hybrid sensor kinase and two response regulators, with no apparent DNA binding domain associated with any of the three proteins encoded by these genes. In this study, we showed that the membrane-bound full-length kinase undergoes autophosphorylation and transfers phosphate to both response regulators. A soluble, truncated version of the kinase was subsequently prepared and found to catalyze phosphorylation of response regulator 1 but not response regulator 2, implying that conformational changes and/or sequence-specific regions of the kinase are important for discriminating between the two response regulators. Analyses indicated that a complex network of control of gene expression must occur, with CbbR required for the expression of the cbbLS genes but dispensable for the synthesis of form II RubisCO (encoded by cbbM). The CbbRRS proteins specifically affected the activity and accumulation of form I RubisCO (CbbLS), as revealed by analyses of nonpolar, unmarked gene deletions. A tentative model of regulation suggested that changes in the phosphotransfer activity of the sensor kinase, possibly in response to a redox metabolic signal, cause modulation of the activity and synthesis of form I RubisCO.

scholarly journals In the Staphylococcus aureus Two-Component System sae, the Response Regulator SaeR Binds to a Direct Repeat Sequence and DNA Binding Requires Phosphorylation by the Sensor Kinase SaeS

2010 ◽  
Vol 192 (8) ◽  
pp. 2111-2127 ◽  
Author(s):  
Fei Sun ◽  
Chunling Li ◽  
Dowon Jeong ◽  
Changmo Sohn ◽  
Chuan He ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Dna Binding ◽  
Response Regulator ◽  
Direct Repeat ◽  
Repeat Sequence ◽  
Sensor Kinase ◽  
Two Component System ◽  
Component System ◽  
Direct Repeat Sequence ◽  
Two Component

ABSTRACT Staphylococcus aureus uses the SaeRS two-component system to control the expression of many virulence factors such as alpha-hemolysin and coagulase; however, the molecular mechanism of this signaling has not yet been elucidated. Here, using the P1 promoter of the sae operon as a model target DNA, we demonstrated that the unphosphorylated response regulator SaeR does not bind to the P1 promoter DNA, while its C-terminal DNA binding domain alone does. The DNA binding activity of full-length SaeR could be restored by sensor kinase SaeS-induced phosphorylation. Phosphorylated SaeR is more resistant to digestion by trypsin, suggesting conformational changes. DNase I footprinting assays revealed that the SaeR protection region in the P1 promoter contains a direct repeat sequence (GTTAAN6GTTAA [where N is any nucleotide]). This sequence is critical to the binding of phosphorylated SaeR. Mutational changes in the repeat sequence greatly reduced both the in vitro binding of SaeR and the in vivo function of the P1 promoter. From these results, we concluded that SaeR recognizes the direct repeat sequence as a binding site and that binding requires phosphorylation by SaeS.

scholarly journals Effect of d-Lactate on the Physiological Activity of the ArcB Sensor Kinase in Escherichia coli

2004 ◽  
Vol 186 (7) ◽  
pp. 2085-2090 ◽  
Author(s):  
Claudia Rodriguez ◽  
Ohsuk Kwon ◽  
Dimitris Georgellis
Keyword(s):  
Kinase Activity ◽  
Response Regulator ◽  
Physiological Activity ◽  
Growth Conditions ◽  
Sensor Kinase ◽  
Two Component System ◽  
Direct Signal ◽  
Two Component

ABSTRACT The Arc two-component system, comprising the ArcB sensor kinase and the ArcA response regulator, modulates the expression of numerous genes in response to the respiratory growth conditions. Under anoxic growth conditions ArcB autophosphorylates and transphosphorylates ArcA, which in turn represses or activates its target operons. The anaerobic metabolite d-lactate has been shown to stimulate the in vitro autophosphorylating activity of ArcB. In this study, the in vivo effect of d-lactate on the kinase activity of ArcB was assessed. The results demonstrate that d-lactate does not act as a direct signal for activation of ArcB, as previously proposed, but acts as a physiologically significant effector that amplifies ArcB kinase activity.

scholarly journals PhoB transcriptional activator binds hierarchically to pho box promoters

2012 ◽  
Vol 393 (10) ◽  
pp. 1165-1171 ◽  
Author(s):  
Alexandre G. Blanco ◽  
Albert Canals ◽  
Miquel Coll
Keyword(s):  
Crystal Structure ◽  
Molecular Mechanisms ◽  
Phosphate Uptake ◽  
Response Regulator ◽  
Sensor Kinase ◽  
Two Component System ◽  
Component System ◽  
Dna Binding Domains ◽  
Binding Domains ◽  
Two Component

Abstract The PhoR-PhoB phosphorelay is a bacterial two-component system that activates the transcription of several genes involved in phosphate uptake and assimilation. The response begins with the autophosphorylation of the sensor kinase PhoR, which activates the response regulator PhoB. Upon binding to the pho box DNA sequence, PhoB recruits the RNA polymerase and thereby activates the transcription of specific genes. To unveil hitherto unknown molecular mechanisms along the activation pathway, we report biochemical data characterizing the PhoB binding to promoters containing multiple pho boxes and describe the crystal structure of two PhoB DNA-binding domains bound in tandem to a 26-mer DNA.

scholarly journals Phosphorelay as the Sole Physiological Route of Signal Transmission by the Arc Two-Component System ofEscherichia coli

2000 ◽  
Vol 182 (13) ◽  
pp. 3858-3862 ◽  
Author(s):  
Ohsuk Kwon ◽  
Dimitris Georgellis ◽  
E. C. C. Lin
Keyword(s):  
Response Regulator ◽  
Signal Transmission ◽  
Phosphoryl Group ◽  
Sensor Kinase ◽  
Wild Type ◽  
Two Component System ◽  
Component System ◽  
Group Transfer ◽  
Two Component

ABSTRACT The Arc two-component system, comprising a tripartite sensor kinase (ArcB) and a response regulator (ArcA), modulates the expression of numerous genes involved in respiratory functions. In this study, the steps of phosphoryl group transfer from phosphorylated ArcB to ArcA were examined in vivo by using single copies of wild-type and mutantarcB alleles. The results indicate that the signal transmission occurs solely by His-Asp-His-Asp phosphorelay.

scholarly journals Phosphotransfer Reactions of the CbbRRS Three-Protein Two- Component System from Rhodopseudomonas palustris CGA010 Appear To Be Controlled by an Internal Molecular Switch on the Sensor Kinase

2006 ◽  
Vol 189 (2) ◽  
pp. 325-335 ◽  
Author(s):  
Simona Romagnoli ◽  
F. Robert Tabita
Keyword(s):  
Response Regulator ◽  
Rhodopseudomonas Palustris ◽  
Molecular Switch ◽  
Sensor Kinase ◽  
Two Component System ◽  
Conserved Residues ◽  
Component System ◽  
Receiver Domain ◽  
Two Component

ABSTRACT The CbbRRS system is an atypical three-protein two-component system that modulates the expression of the cbb I CO2 fixation operon of Rhodopseudomonas palustris, possibly in response to a redox signal. It consists of a membrane-bound hybrid sensor kinase, CbbSR, with a transmitter and receiver domain, and two response regulator proteins, CbbRR1 and CbbRR2. No detectable helix-turn-helix DNA binding domain is associated with either response regulator, but an HPt domain and a second receiver domain are predicted at the C-terminal region of CbbRR1 and CbbRR2, respectively. The abundance of conserved residues predicted to participate in a His-Asp phosphorelay raised the question of their de facto involvement. In this study, the role of the multiple receiver domains was elucidated in vitro by generating site-directed mutants of the putative conserved residues. Distinct phosphorylation patterns were obtained with two truncated versions of the hybrid sensor kinase, CbbSRT189 and CbbSRR96 (CbbSR beginning at residues T189 and R96, respectively). These constructs also exhibited substantially different affinities for ATP and phosphorylation stability, which was found to be dependent on a conserved Asp residue (Asp-696) within the kinase receiver domain. Asp-696 also played an important role in defining the specificity of phosphorylation for response regulators CbbRR1 or CbbRR2, and this residue appeared to act in conjunction with residues within the region from Arg-96 to Thr-189 at the N terminus of the sensor kinase. The net effect of concerted interactions at these distinct regions of CbbSR created an internal molecular switch that appears to coordinate a unique branched phosphorelay system.

scholarly journals PhoR1-PhoP1, a Third Two-Component System of the Family PhoRP from Myxococcus xanthus: Role in Development

2005 ◽  
Vol 187 (14) ◽  
pp. 4976-4983 ◽  
Author(s):  
Juana Carrero-Lérida ◽  
Aurelio Moraleda-Muñoz ◽  
Raquel García-Hernández ◽  
Juana Pérez ◽  
José Muñoz-Dorado
Keyword(s):  
Transmembrane Domain ◽  
Response Regulator ◽  
Two Component System ◽  
Alkaline Phosphatases ◽  
Histidine Kinases ◽  
Component System ◽  
Amino Terminal ◽  
Helix Loop Helix ◽  
The Family ◽  
Two Component

ABSTRACT The pair PhoR1-PhoP1 is the third two-component system of the family PhoRP reported in M. xanthus. PhoR1 is a histidine kinase anchored to the membrane through a transmembrane domain located in the amino-terminal portion of the protein. As a result, 93% of the protein is located in the cytoplasm. This topology is unusual in the PhoR-type histidine kinases. PhoP1 is a response regulator with a helix-loop-helix motif typical of the DNA-binding proteins. Although the operon phoPR1 is expressed during vegetative growth, it peaks during development. The expression levels of this operon are higher in phosphate-containing media than in those in which the nutrient is absent. A deletion mutant in this system exhibits a delay in aggregation and the formation of fruiting bodies larger than those of the wild-type strain. The expression of the operon is autoregulated. This system is also partially responsible for the expression of Mg-independent acid and neutral phosphatases, but it is not required for the expression of alkaline phosphatases.

scholarly journals Functional Analysis of theMycobacterium tuberculosis MprAB Two-Component SignalTransductionSystem

2003 ◽  
Vol 71 (12) ◽  
pp. 6962-6970 ◽  
Author(s):  
Thomas C. Zahrt ◽  
Christopher Wozniak ◽  
Denise Jones ◽  
Andrea Trevett
Keyword(s):  
Signal Transduction ◽  
Functional Analysis ◽  
Persistent Infection ◽  
Response Regulator ◽  
Sensor Kinase ◽  
Two Component System ◽  
Two Component ◽  
Two Component Signal Transduction

ABSTRACT The mechanisms utilized by Mycobacterium tuberculosis to establish, maintain, or reactivate from latent infection in the host are largely unknown but likely include genes that mediate adaptation to conditions encountered during persistence. Previously, a two-component signal transduction system, mprAB, was found to be required in M. tuberculosis for establishment and maintenance of persistent infection in a tissue- and stage-specific fashion. To begin to characterize the role of this system in M. tuberculosis physiology and virulence, a functional analysis of the mprA and mprB gene products was initiated. Here, evidence is presented demonstrating that sensor kinase MprB and response regulator MprA function as an intact signal-transducing pair in vitro and in vivo. Sensor kinase MprB can be autophosphorylated, can donate phosphate to MprA, and can act as a phospho-MprA phosphatase in vitro. Correspondingly, response regulator MprA can accept phosphate from MprB or from small phosphodonors including acetyl phosphate. Mutagenesis of residues His249 in MprB and Asp48 in MprA abolished the ability of these proteins to be phosphorylated in vitro. Introduction of these alleles into Mycobacterium bovis BCGattenuated virulence in macrophages in vivo. Together, these results support a role for the mprAB two-component system in M. tuberculosis physiology and pathogenesis. Characterization of two-component signal transduction systems will enhance our understanding of processes regulated by M. tuberculosis during acute and/or persistent infection in the host.

Sign in / Sign up

Export Citation Format

Share Document