Identification of a DtxR-Regulated Operon That Is Essential for Siderophore-Dependent Iron Uptake in Corynebacterium diphtheriae

@article{Qian2002IdentificationOA,
  title={Identification of a DtxR-Regulated Operon That Is Essential for Siderophore-Dependent Iron Uptake in Corynebacterium diphtheriae},
  author={Yilei Qian and John-hwa Lee and Randall K. Holmes},
  journal={Journal of Bacteriology},
  year={2002},
  volume={184},
  pages={4846 - 4856}
}
ABSTRACT The diphtheria toxin repressor (DtxR) uses Fe2+ as a corepressor and inhibits transcription from iron-regulated promoters (IRPs) in Corynebacterium diphtheriae. A new IRP, designated IRP6, was cloned from C. diphtheriae by a SELEX-like procedure. DtxR bound to IRP6 in vitro only in the presence of appropriate divalent metal ions, and repression of IRP6 by DtxR in an Escherichia coli system was iron dependent. The open reading frames (ORFs) downstream from IRP6 and previously described… 
Analysis of a DtxR-Regulated Iron Transport and Siderophore Biosynthesis Gene Cluster in Corynebacterium diphtheriae
TLDR
A genetic locus associated with siderophore biosynthesis and transport in Corynebacterium diphtheriae is described, which demonstrated that expression of ciuA and ciuE is DtxR and iron regulated, and DNase I protection experiments confirmed the presence of D txR binding sites upstream from each of these genes.
Analysis of the Corynebacterium diphtheriae DtxR Regulon: Identification of a Putative Siderophore Synthesis and Transport System That Is Similar to the Yersinia High-Pathogenicity Island-Encoded Yersiniabactin Synthesis and Uptake System
TLDR
The findings from this study indicate that C. diphtheriae contains at least 18 DtxR binding sites and that D txR may affect the expression of as many as 40 genes.
Prediction of DtxR regulon: Identification of binding sites and operons controlled by Diphtheria toxin repressor in Corynebacterium diphtheriae
TLDR
The analysis shows that DtxR could provide a molecular link between Fe+2-induced Fenton's reaction and protection of DNA from oxidative damage and play an important role in host interaction and virulence by regulating the levels of sortase, a potential vaccine candidate and proteins of secretory system.
HtaA Is an Iron-Regulated Hemin Binding Protein Involved in the Utilization of Heme Iron in Corynebacterium diphtheriae
TLDR
Hemin binding studies demonstrated that HtaA and HtaB are able to bind hemin, suggesting that these proteins may function as cell surface hemin receptors in C. diphtheriae.
Analysis of a DtxR-Like Metalloregulatory Protein, MntR, from Corynebacterium diphtheriae That Controls Expression of an ABC Metal Transporter by an Mn2+-Dependent Mechanism
TLDR
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Analysis of a Heme-Dependent Signal Transduction System in Corynebacterium diphtheriae: Deletion of the chrAS Genes Results in Heme Sensitivity and Diminished Heme-Dependent Activation of the hmuO Promoter
TLDR
The heme sensitivity of the mutants was not due to reduced expression of hmuO, and these results suggest that additional factors controlled by the ChrA/S system may be involved in protection against heme toxicity.
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TLDR
These studies provide the first quantitative transcriptional analysis of a gene encoding a DtxR family regulator and give new insights into transcriptional regulation in C. diphtheriae.
Computational prediction of DtxR regulon - a dissection of physiological process controlled by DtxR in Corynebacterium species
TLDR
A user friendly software tool to identify the potential binding sites of any regulatory protein based on Shannon relative entropy method predicted the binding sites upstream to a number of genes/operons which code for proteins involved in hemolysis and haemin transport.
Proteomic analysis reveals the wide-ranging effects of the novel, iron-responsive regulator RirA in Rhizobium leguminosarum bv. viciae
TLDR
Although RirA shows no sequence similarity to Fur or DtxR, it functions as a wide-ranging, Fe-responsive regulator that regulates gene expression in Rhizobium leguminosarum bv.
Regulation of MntH by a Dual Mn(II)- and Fe(II)-Dependent Transcriptional Repressor (DR2539) in Deinococcus radiodurans
TLDR
This study suggests that D. radiodurans has evolved a very efficient manganese regulation mechanism that involves its high intracellular Mn/Fe ratio and permits resistance to extreme conditions.
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TLDR
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TLDR
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TLDR
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