scholarly journals Positive and Negative Transcriptional Regulation of the Escherichia coli Gluconate Regulon Gene gntTby GntR and the Cyclic AMP (cAMP)-cAMP Receptor Protein Complex

1998 ◽  
Vol 180 (7) ◽  
pp. 1777-1785 ◽  
Author(s):  
Norbert Peekhaus ◽  
T. Conway
Keyword(s):  
Escherichia Coli ◽  
Cyclic Amp ◽  
Catabolite Repression ◽  
Transcriptional Start Site ◽  
Negative Regulator ◽  
Site Directed Mutagenesis ◽  
Receptor Protein ◽  
Start Site ◽  
Camp Receptor Protein ◽  
Camp Receptor

ABSTRACT The gntT gene of Escherichia coli is specifically induced by gluconate and repressed via catabolite repression. Thus, gluconate is both an inducer and a repressor ofgntT expression since gluconate is a catabolite-repressing sugar. In a gntR deletion mutant, the expression of a chromosomal gntT::lacZ fusion is both high and constitutive, confirming that GntR is the negative regulator of gntT. Indeed, GntR binds to two consensus gnt operator sites; one overlaps the −10 region of the gntT promoter, and the other is centered at +120 with respect to the transcriptional start site. The binding of GntR to these sites was proven in vitro by gel redardation assays and in vivo by site-directed mutagenesis of the binding sites. Binding of GntR to the operators is eliminated by gluconate and also by 6-phosphogluconate at a 10-fold-higher concentration. Interestingly, when gntR deletion strains are grown in the presence of gluconate, there is a twofold decrease in gntTexpression which is independent of catabolite repression and binding of GntR to the operator sites. This novel response of gntRmutants to the inducer is termed ultrarepression. Transcription ofgntT is activated by binding of the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex to a CRP binding site positioned at −71 upstream of the gntT transcription start site.

scholarly journals Regulation of ytfK by cAMP-CRP Contributes to SpoT-Dependent Accumulation of (p)ppGpp in Response to Carbon Starvation YtfK Responds to Glucose Exhaustion

2021 ◽  
Vol 12 ◽  
Author(s):  
Laura Meyer ◽  
Elsa Germain ◽  
Etienne Maisonneuve
Keyword(s):  
Escherichia Coli ◽  
Cyclic Amp ◽  
Catabolite Repression ◽  
Stringent Response ◽  
Receptor Protein ◽  
Glucose Starvation ◽  
Camp Receptor Protein ◽  
E Coli ◽  
Camp Receptor ◽  
Glucose Availability

Guanosine penta- or tetraphosphate (known as (p)ppGpp) serves as second messenger to respond to nutrient downshift and other environmental stresses, a phenomenon called stringent response. Accumulation of (p)ppGpp promotes the coordinated inhibition of macromolecule synthesis, as well as the activation of stress response pathways to cope and adapt to harmful conditions. In Escherichia coli, the (p)ppGpp level is tightly regulated by two enzymes, the (p)ppGpp synthetase RelA and the bifunctional synthetase/hydrolase SpoT. We recently identified the small protein YtfK as a key regulator of SpoT-mediated activation of stringent response in E. coli. Here, we further characterized the regulation of ytfK. We observed that ytfK is subjected to catabolite repression and is positively regulated by the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex. Importantly, YtfK contributes to SpoT-dependent accumulation of (p)ppGpp and cell survival in response to glucose starvation. Therefore, regulation of ytfK by the cAMP-CRP appears important to adjust (p)ppGpp level and coordinate cellular metabolism in response to glucose availability.

scholarly journals Catabolite Repression of Escherichia coli Biofilm Formation

2002 ◽  
Vol 184 (12) ◽  
pp. 3406-3410 ◽  
Author(s):  
Debra W. Jackson ◽  
Jerry W. Simecka ◽  
Tony Romeo
Keyword(s):  
Escherichia Coli ◽  
Cyclic Amp ◽  
Catabolite Repression ◽  
Biofilm Formation ◽  
Protein A ◽  
Receptor Protein ◽  
Camp Receptor Protein ◽  
Glucose Addition ◽  
Camp Receptor ◽  
Biofilm Development

ABSTRACT Biofilm formation was repressed by glucose in several species of Enterobacteriaceae. In Escherichia coli, this effect was mediated at least in part by cyclic AMP (cAMP)-cAMP receptor protein. A temporal role for cAMP in biofilm development was indicated by the finding that glucose addition after ∼24 h failed to repress and generally activated biofilm formation.

scholarly journals Cyclic AMP (cAMP) Receptor Protein-cAMP Complex Regulates Heparosan Production in Escherichia coli Strain Nissle 1917

2015 ◽  
Vol 81 (22) ◽  
pp. 7687-7696 ◽  
Author(s):  
Huihui Yan ◽  
Feifei Bao ◽  
Liping Zhao ◽  
Yanying Yu ◽  
Jiaqin Tang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Cyclic Amp ◽  
Carbon Sources ◽  
Coli Strain ◽  
Site Directed Mutagenesis ◽  
Receptor Protein ◽  
Upstream Region ◽  
Camp Receptor Protein ◽  
Content Type ◽  
Camp Receptor

ABSTRACTHeparosan serves as the starting carbon backbone for the chemoenzymatic synthesis of heparin, a widely used clinical anticoagulant drug. The availability of heparosan is a significant concern for the cost-effective synthesis of bioengineered heparin. The carbon source is known as the pivotal factor affecting heparosan production. However, the mechanism by which carbon sources control the biosynthesis of heparosan is unclear. In this study, we found that the biosynthesis of heparosan was influenced by different carbon sources. Glucose inhibits the biosynthesis of heparosan, while the addition of either fructose or mannose increases the yield of heparosan. Further study demonstrated that the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex binds to the upstream region of the region 3 promoter and stimulates the transcription of the gene cluster for heparosan biosynthesis. Site-directed mutagenesis of the CRP binding site abolished its capability of binding CRP and eliminated the stimulative effect on transcription.1H nuclear magnetic resonance (NMR) analysis was further performed to determine theEscherichia colistrain Nissle 1917 (EcN) heparosan structure and quantify extracellular heparosan production. Our results add to the understanding of the regulation of heparosan biosynthesis and may contribute to the study of other exopolysaccharide-producing strains.

scholarly journals The cyclic AMP (cAMP)-cAMP receptor protein complex functions both as an activator and as a corepressor at the tsx-p2 promoter of Escherichia coli K-12.

1991 ◽  
Vol 173 (17) ◽  
pp. 5419-5430 ◽  
Author(s):  
P Gerlach ◽  
L Søgaard-Andersen ◽  
H Pedersen ◽  
J Martinussen ◽  
P Valentin-Hansen ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Cyclic Amp ◽  
Protein Complex ◽  
Receptor Protein ◽  
Camp Receptor Protein ◽  
Complex Functions ◽  
P2 Promoter ◽  
Camp Receptor ◽  
K 12

scholarly journals Dual Transcriptional Regulation of theEscherichia coli Phosphate-Starvation-InduciblepsiE Gene of the Phosphate Regulon by PhoB and the Cyclic AMP (cAMP)-cAMP Receptor Protein Complex

2000 ◽  
Vol 182 (19) ◽  
pp. 5596-5599 ◽  
Author(s):  
Soo-Ki Kim ◽  
Sigenobu Kimura ◽  
Hideo Shinagawa ◽  
Atsuo Nakata ◽  
Ki-Sung Lee ◽  
...  
Keyword(s):  
Cyclic Amp ◽  
Transcriptional Start Site ◽  
Phosphate Starvation ◽  
Negative Control ◽  
Receptor Protein ◽  
Camp Receptor Protein ◽  
Dnase I Footprinting ◽  
Transcriptional Activator Protein ◽  
Camp Receptor

ABSTRACT We have shown that the Escherichia coliphosphate-starvation-inducible psiE gene is regulated by both phosphate and the carbon source by using both lacZ and chloramphenicol acetyltransferase gene (cat) fusions. Yet, under all conditions tested, a single transcriptional start site lying 7 bp downstream of a predicted −10 region was revealed by primer extension analysis. DNase I footprinting showed that the PhoB transcriptional-activator protein protects two predictedpho boxes lying upstream of and near the −35 promoter region. Similar analysis showed that the cyclic AMP (cAMP)-cAMP receptor protein (cAMP-CRP) complex binds a region that overlaps with the downstream pho box. These results, together with measurements of the in vivo psiE promoter activity under various conditions, show that expression of the psiE gene is under direct positive and negative control by PhoB and cAMP-CRP, respectively.

scholarly journals Negative Regulation of IS2 Transposition by the Cyclic AMP (cAMP)-cAMP Receptor Protein Complex

1998 ◽  
Vol 180 (10) ◽  
pp. 2682-2688 ◽  
Author(s):  
Shiau-Ting Hu ◽  
Hsuan-Chen Wang ◽  
Guang-Sheng Lei ◽  
Shao-Hung Wang
Keyword(s):  
Cyclic Amp ◽  
Negative Regulator ◽  
Receptor Protein ◽  
Camp Receptor Protein ◽  
Fusion Construct ◽  
Dna Footprinting ◽  
Gel Retardation Assay ◽  
Consensus Binding Sequence ◽  
Camp Receptor ◽  
Binding Sequence

ABSTRACT Three sequences similar to that of the consensus binding sequence of the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex were found in the major IS2 promoter region. Experiments were performed to determine whether the cAMP-CRP complex plays a role in the regulation of IS2 transposition. In the gel retardation assay, the cAMP-CRP complex was found to be able to bind the major IS2 promoter. A DNA footprinting assay confirmed that the cAMP-CRP complex binds to the sequences mentioned above. With an IS2 promoter-luciferase gene fusion construct, the cAMP-CRP complex was shown to inhibit transcription from the major IS2 promoter. IS2 was found to transpose at a frequency approximately 200-fold higher in an Escherichia coli host defective for CRP or adenyl cyclase than in a wild-type host. These results suggest that the cAMP-CRP complex is a negative regulator of IS2 transposition.

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