Spontaneous Subunit Exchange and Biochemical Evidence for Trans-autophosphorylation in a Dimer of Escherichia coli Histidine Kinase (EnvZ)

Cai, Sheng-Jian; Inouye, Masayori

doi:10.1016/s0022-2836(03)00446-7

Cited by 40 publications

(40 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This mechanism is demonstrable in vitro for NtrB (Ninfa et al, 1993), CheA (Swanson et al, 1993) and EnvZ (Cai & Inouye, 2003) among others. However, intramolecular phosphate transfer within a subunit was later observed for PhoR, HK853 (Casino et al, 2009) and ArcB (Peña-Sandoval & Georgellis, 2010).…”

Section: Narx and Narq Sensors Undergo Intermolecular Autophosphorylamentioning

confidence: 83%

Sensor–response regulator interactions in a cross-regulated signal transduction network

2015

View full text Add to dashboard Cite

Two-component signal transduction involves phosphoryl transfer between a histidine kinase sensor and a response regulator effector. The nitrate-responsive two-component signal transduction systems in Escherichia coli represent a paradigm for a cross-regulation network, in which the paralogous sensor-response regulator pairs, NarX-NarL and NarQ-NarP, exhibit both cognate (e.g. NarX-NarL) and non-cognate (e.g. NarQ-NarL) interactions to control output. Here, we describe results from bacterial adenylate cyclase two-hybrid (BACTH) analysis to examine sensor dimerization as well as interaction between sensor-response regulator cognate and non-cognate pairs. Although results from BACTH analysis indicated that the NarX and NarQ sensors interact with each other, results from intragenic complementation tests demonstrate that they do not form functional heterodimers. Additionally, intragenic complementation shows that both NarX and NarQ undergo intermolecular autophosphorylation, deviating from the previously reported correlation between DHp (dimerization and histidyl phosphotransfer) domain loop handedness and autophosphorylation mode. Results from BACTH analysis revealed robust interactions for the NarX-NarL, NarQ-NarL and NarQ-NarP pairs but a much weaker interaction for the NarX-NarP pair. This demonstrates that asymmetrical cross-regulation results from differential binding affinities between different sensor-regulator pairs. Finally, results indicate that the NarL effector (DNA-binding) domain inhibits NarX-NarL interaction. Missense substitutions at receiver domain residue Ser-80 enhanced NarX-NarL interaction, apparently by destabilizing the NarL receiver-effector domain interface.

show abstract

Section: Narx and Narq Sensors Undergo Intermolecular Autophosphorylamentioning

confidence: 83%

Sensor–response regulator interactions in a cross-regulated signal transduction network

2015

View full text Add to dashboard Cite

show abstract

“…In terms of the autophosphorylation mechanism, some HKs like EnvZ and NtrB (10,11) autophosphorylate following a trans pathway, i.e. one monomer phosphorylating the histidine of the other.…”

mentioning

confidence: 99%

Structural and Enzymatic Insights into the ATP Binding and Autophosphorylation Mechanism of a Sensor Histidine Kinase

Trajtenberg¹,

Graña

Ruétalo³

et al. 2010

Journal of Biological Chemistry

View full text Add to dashboard Cite

DesK is a sensor histidine kinase (HK) that allows Bacillus subtilis to respond to cold shock, triggering the adaptation of membrane fluidity via transcriptional control of a fatty acid desaturase. It belongs to the HK family HPK7, which includes the nitrogen metabolism regulators NarX/Q and the antibiotic sensor LiaS among other important sensor kinases. Structural information on different HK families is still scarce and several questions remain, particularly concerning the molecular features that determine HK specificity during its catalytic autophosphorylation and subsequent response-regulator phosphotransfer reactions. To analyze the ATP-binding features of HPK7 HKs and dissect their mechanism of autophosphorylation at the molecular level, we have studied DesK in complex with ATP using high resolution structural approaches in combination with biochemical studies. We report the first crystal structure of an HK in complex with its natural nucleotidic substrate. The general fold of the ATP-binding domain of DesK is conserved, compared with well studied members of other families. Yet, DesK displays a far more compact structure at the ATP-binding pocket: the ATP lid loop is much shorter with no secondary structural organization and becomes ordered upon ATP loading. Sequence conservation mapping onto the molecular surface, semi-flexible protein-protein docking simulations, and structure-based point mutagenesis allow us to propose a specific domain-domain geometry during autophosphorylation catalysis. Supporting our hypotheses, we have been able to trap an autophosphorylating intermediate state, by protein engineering at the predicted domain-domain interaction surface.

show abstract

“…The VirA dimer appears to be a key structural element that is linked to at least two aspects of signal transduction. First, it has been demonstrated for several histidine kinases, including VirA, that autophosphorylation is an intersubunit reaction, whereby a phosphate group is transferred from the catalytic region on one dimer subunit to a conserved histidine on the second subunit (5,6,27,37,45). Second, the stabilizing influence of the leucine zipper has been used in fusions to VirA and Tar to demonstrate that a particular orientation at the linker interface between dimer subunits correlates with signal-transducing activity (11,39).…”

mentioning

confidence: 99%

Intersubunit Complementation of Sugar Signal Transduction in VirA Heterodimers and Posttranslational Regulation of VirA Activity inAgrobacterium tumefaciens

2005

View full text Add to dashboard Cite

The VirA/VirG two-component regulatory system of Agrobacterium tumefaciens regulates expression of the virulence (vir) genes that control the infection process leading to crown gall tumor disease on susceptible plants. VirA, a membrane-bound homodimer, initiates vir gene induction by communicating the presence of molecular signals found at the site of a plant wound through phosphorylation of VirG. Inducing signals include phenols, monosaccharides, and acidic pH. While sugars are not essential for gene induction, their presence greatly increases vir gene expression when levels of the essential phenolic signal are low. Reception of the sugar signal depends on a direct interaction between ChvE, a sugar-binding protein, and VirA. Here we show that the sugar signal received in the periplasmic region of one subunit within a VirA heterodimer can enhance the kinase function of the second subunit. However, sugar enhancement of vir gene expression was vector dependent. virA alleles expressed from pSa-derived vectors inhibited signal transduction by endogenous VirA. Inhibition was conditional, depending on the induction medium and the virA allele tested. Moreover, constitutive expression of virG overcame the inhibitory effect of some but not all virA alleles, suggesting that there may be more than one inhibitory mechanism.

show abstract

Spontaneous Subunit Exchange and Biochemical Evidence for Trans-autophosphorylation in a Dimer of Escherichia coli Histidine Kinase (EnvZ)

Cited by 40 publications

References 28 publications

Sensor–response regulator interactions in a cross-regulated signal transduction network

Sensor–response regulator interactions in a cross-regulated signal transduction network

Structural and Enzymatic Insights into the ATP Binding and Autophosphorylation Mechanism of a Sensor Histidine Kinase

Intersubunit Complementation of Sugar Signal Transduction in VirA Heterodimers and Posttranslational Regulation of VirA Activity inAgrobacterium tumefaciens

Contact Info

Product

Resources

About