A 750 bp sensory integration region directs global control of the <i>Escherichia coli</i> GadE acid resistance regulator

Sayed, Atef K.; Foster, John W.

doi:10.1111/j.1365-2958.2009.06614.x

Cited by 52 publications

(74 citation statements)

References 54 publications

(85 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One of the main elements in this control is the availability of the interaction partners. Expression of all of the corresponding genes is repressed by the nucleoid-associated and global repressor protein H-NS (22,47,54,55) (Fig. 7).…”

Section: Discussionmentioning

confidence: 99%

Interaction of the RcsB Response Regulator with Auxiliary Transcription Regulators in Escherichia coli

Pannen

Fabisch

Gausling

et al. 2016

Journal of Biological Chemistry

View full text Add to dashboard Cite

The Rcs phosphorelay is a two-component signal transduction system that is induced by cell envelope stress. RcsB, the response regulator of this signaling system, is a pleiotropic transcription regulator, which is involved in the control of various stress responses, cell division, motility, and biofilm formation. RcsB regulates transcription either as a homodimer or together with auxiliary regulators, such as RcsA, BglJ, and GadE in Escherichia coli. In this study, we show that RcsB in addition forms heterodimers with MatA (also known as EcpR) and with DctR. Our data suggest that the MatA-dependent transcription regulation is mediated by the MatA-RcsB heterodimer and is independent of RcsB phosphorylation. Furthermore, we analyzed the relevance of amino acid residues of the active quintet of conserved residues, and of surface-exposed residues for activity of RcsB. The data suggest that the activity of the phosphorylation-dependent dimers, such as RcsA-RcsB and RcsB-RcsB, is affected by mutation of residues in the vicinity of the phosphorylation site, suggesting that a phosphorylation-induced structural change modulates their activity. In contrast, the phosphorylation-independent heterodimers BglJ-RcsB and MatA-RcsB are affected by only very few mutations. Heterodimerization of RcsB with various auxiliary regulators and their differential dependence on phosphorylation add an additional level of control to the Rcs system that is operating at the output level.

show abstract

Section: Discussionmentioning

confidence: 99%

Interaction of the RcsB Response Regulator with Auxiliary Transcription Regulators in Escherichia coli

Pannen

Fabisch

Gausling

et al. 2016

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…Overall, the microarray analysis revealed that the most dramatically affected of all genes were gadA, gadB, gadC, and gadE (see Table S3 in the supplemental material). The gadE gene product is a luxR family transcriptional regulator of the gadABC operon (18,37,42). The gadA gene encodes glutamic acid decarboxylase; gadE-gadABC regulation is induced by acid and salt shock and is sensitive to RpoS, EvgAS, and H-NS regulation.…”

Section: Without Amino Acidsmentioning

confidence: 99%

Effects on Growth by Changes of the Balance between GreA, GreB, and DksA Suggest Mutual Competition and Functional Redundancy in Escherichia coli

et al. 2012

View full text Add to dashboard Cite

It is well known that ppGpp and DksA interact with bacterial RNA polymerase (RNAP) to alter promoter activity. This study suggests that GreA plays a major role and GreB plays a minor role in the ppGpp-DksA regulatory network. We present evidence that DksA and GreA/GreB are redundant and/or share similar functions: (i) on minimal medium GreA overproduction suppresses the growth defects of a dksA mutant; (ii) GreA and DksA overexpression partially suppresses the auxotrophy of a ppGppdeficient strain; (iii) microarrays show that many genes are regulated similarly by GreA and DksA. We also find instances where GreA and DksA seem to act in opposition: (i) complete suppression of auxotrophy occurs by overexpression of GreA or DksA only in the absence of the other protein; (ii) PgadA and PgadE promoter fusions, along with many other genes, are dramatically affected in vivo by GreA overproduction only when DksA is absent; (iii) GreA and DksA show opposite regulation of a subset of genes. Mutations in key acidic residues of GreA and DksA suggest that properties seen here probably are not explained by known biochemical activities of these proteins. Our results indicate that the general pattern of gene expression and, in turn, the ability of Escherichia coli to grow under a defined condition are the result of a complex interplay between GreA, GreB, and DksA that also involves mutual control of their gene expression, competition for RNA polymerase binding, and similar or opposite action on RNA polymerase activity.

show abstract

“…A, shown is a diagram of the gadE-mdtEF operon. Three promoter regions (P1, P2, and P3) and corresponding transcription starting sites (21) relative to the ATG start codon of gadE are indicated. A putative ArcA binding site is identified upstream of the Ϫ324 transcription starting site.…”

Section: Mdtef Increases the Efflux Activity In Anaerobic E Coli Cells-mentioning

confidence: 99%

The Multidrug Efflux Pump MdtEF Protects against Nitrosative Damage during the Anaerobic Respiration in Escherichia coli

Zhang

Xiao

Horiyama

et al. 2011

Journal of Biological Chemistry

View full text Add to dashboard Cite

Drug efflux represents an important protection mechanism in bacteria to withstand antibiotics and environmental toxic substances. Efflux genes constitute 6 -18% of all transporters in bacterial genomes, yet the expression and functions of only a handful of them have been studied. Among the 20 efflux genes encoded in the Escherichia coli K-12 genome, only the AcrABTolC system is constitutively expressed. The expression, activities, and physiological functions of the remaining efflux genes are poorly understood. In this study we identified a dramatic up-regulation of an additional efflux pump, MdtEF, under the anaerobic growth condition of E. coli, which is independent of antibiotic exposure. We found that expression of MdtEF is upregulated more than 20-fold under anaerobic conditions by the global transcription factor ArcA, resulting in increased efflux activity and enhanced drug tolerance in anaerobically grown E. coli. Cells lacking mdtEF display a significantly decreased survival rate under the condition of anaerobic respiration of nitrate. Deletion of the genes responsible for the biosynthesis of indole, tnaAB, or replacing nitrate with fumarate as the terminal electron acceptor during the anaerobic respiration restores the decreased survival of ⌬mdtEF cells. Moreover, ⌬mdtEF cells are susceptible to indole nitrosative derivatives, a class of toxic byproducts formed and accumulated within E. coli when the bacterium respires nitrate under anaerobic conditions. Taken together, we conclude that the multidrug efflux pump MdtEF is up-regulated during the anaerobic physiology of E. coli to protect the bacterium from nitrosative damage through expelling the nitrosyl indole derivatives out of the cells.

show abstract

A 750 bp sensory integration region directs global control of the Escherichia coli GadE acid resistance regulator

Cited by 52 publications

References 54 publications

Interaction of the RcsB Response Regulator with Auxiliary Transcription Regulators in Escherichia coli

Interaction of the RcsB Response Regulator with Auxiliary Transcription Regulators in Escherichia coli

Effects on Growth by Changes of the Balance between GreA, GreB, and DksA Suggest Mutual Competition and Functional Redundancy in Escherichia coli

The Multidrug Efflux Pump MdtEF Protects against Nitrosative Damage during the Anaerobic Respiration in Escherichia coli

Contact Info

Product

Resources

About