Transcriptional regulation in response to oxygen and nitrate of the operons encoding the [NiFe] hydrogenases 1 and 2 of Escherichia coli.

@article{Richard1999TranscriptionalRI,
  title={Transcriptional regulation in response to oxygen and nitrate of the operons encoding the [NiFe] hydrogenases 1 and 2 of Escherichia coli.},
  author={Dutton Richard and Gary Sawers and Frank Sargent and L McWalter and David H. Boxer},
  journal={Microbiology},
  year={1999},
  volume={145 ( Pt 10)},
  pages={
          2903-12
        }
}
Synthesis of the [NiFe] hydrogenases 1 and 2 of Escherichia coli is induced in response to anaerobiosis and is repressed when nitrate is present in the growth medium. The hydrogenase 1 and hydrogenase 2 enzymes are encoded by the polycistronic hyaABCDEF and hybOABCDEFG operons, respectively. Primer extension analysis was used to determine the initiation site of transcription of both operons. This permitted the construction of single-copy lacZ operon fusions, which were used to examine the… Expand
An FNR-Type Regulator Controls the Anaerobic Expression of Hyn Hydrogenase in Thiocapsa roseopersicina
TLDR
In vitro experiments with purified E. coli Ala154 FNR protein and purified E coli RNA polymerase showed that FNR bound to two sites in the hyn regulatory region, that F NR could activate transcription initiation at the HynS promoter, and that FNH bound at the two target sites activated to different extents. Expand
ArcA and AppY Antagonize IscR Repression of Hydrogenase-1 Expression under Anaerobic Conditions, Revealing a Novel Mode of O2 Regulation of Gene Expression in Escherichia coli
TLDR
It is reported that ArcA and AppY increase P (hyaA) expression under anaerobic conditions by antagonizing IscR binding at P(hyaA), since iscR repression is observed when either ArcA or AppY is eliminated, and that [2Fe-2S]-IscR is a weaker repressor of P(hyA) than clusterless IscC92A. Expand
The role of the ferric-uptake regulator Fur and iron homeostasis in controlling levels of the [NiFe]-hydrogenases in Escherichia coli
Escherichia coli when growing anaerobically synthesizes three [NiFe]-hydrogenases. We investigated the consequences on hydrogenase levels, enzyme activity and gene expression of deleting the ferricExpand
Differential expression of NiFe uptake-type hydrogenase genes in Salmonella enterica serovar Typhimurium.
TLDR
It is suggested that the three hydrogenase operons hyb, hya and hyd are used under different conditions, likely enhancing the pathogen's capacity to survive in a variety of environments. Expand
Complex Transcriptional Control Links NikABCDE-Dependent Nickel Transport with Hydrogenase Expression in Escherichia coli
TLDR
A nitrate-dependent mechanism for nikABCDE repression that is linked to the NarLX two-component system is identified and shows that it closely correlates with hydrogenase expression levels, suggesting that the hydrogenase assembly pathway is sequestered within the cell. Expand
Genome-Wide Expression Analysis Indicates that FNR of Escherichia coli K-12 Regulates a Large Number of Genes of Unknown Function
TLDR
It is suggested that E. coli MG1655 has a larger metabolic potential under anaerobic conditions than has been previously recognized. Expand
Expression and Regulation of a Silent Operon, hyf, Coding for Hydrogenase 4 Isoenzyme in Escherichia coli
TLDR
The hyf operon of Escherichia coli, noted for encoding the fourth hydrogenase isoenzyme (HYD4), is not expressed at a significant level in a wild-type strain, however, mutant FhlA proteins (constitutive activators of the hyc-encoded hydrogenase 3 isoen enzyme) activated hyf-lacZ. Expand
Differential effects of isc operon mutations on the biosynthesis and activity of key anaerobic metalloenzymes in Escherichia coli.
Escherichia coli has two machineries for the synthesis of FeS clusters, namely Isc (iron-sulfur cluster) and Suf (sulfur formation). The Isc machinery, encoded by the iscRSUA-hscBA-fdx-iscXoperon,Expand
Iron restriction induces preferential down-regulation of H2-consuming over H2-evolving reactions during fermentative growth of Escherichia coli
TLDR
The retention of residual hydrogen-evolving activity, even in the feoB entC double null mutant, suggests that sufficient iron can be scavenged to synthesize this key fermentative enzyme complex in preference to the hydrogen-uptake enzymes. Expand
IscR‐dependent gene expression links iron‐sulphur cluster assembly to the control of O2‐regulated genes in Escherichia coli
TLDR
The findings presented here indicate a more general role of IscR in the regulation of Fe‐S cluster biogenesis and that iscR contributes to the O2 regulation of several promoters controlling the expression of anaerobic Fe‐sulphur proteins. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 45 REFERENCES
Anaerobic regulation of the hydrogenase 1 (hya) operon of Escherichia coli
TLDR
Investigation of the effects of different anaerobic growth conditions on the expression of the hya operon showed that expression was induced by formate and repressed by nitrate, suggesting that hydrogenase isoenzyme 1 has a function during both fermentative growth and an aerobic respiration. Expand
Anaerobic induction of pyruvate formate-lyase gene expression is mediated by the ArcA and FNR proteins
TLDR
Data indicate that both ArcA and FNR are essential for anaerobic activation of promoter 7 transcription, which suggests functional interaction between these proteins. Expand
Effects of sigmaS and the transcriptional activator AppY on induction of the Escherichia coli hya and cbdAB-appA operons in response to carbon and phosphate starvation
TLDR
The induction ratio of the two operons was the same in rpoS+ and rPoS mutant strains, indicating that the phosphate starvation-induced increase in sigmaS concentration is not involved in the phosphate regulation of these operons. Expand
Mechanism of regulation of the formate‐hydrogenlyase pathway by oxygen, nitrate, and pH: definition of the formate regulon
TLDR
Observations indicate that it is the intracellular level of formate that determines the transcription of the genes of the formate regulon by FhlA, a novel positive feedback mechanism in which the activator of a regulon induces its own synthesis in response to increases in the concentration of the catabolic substrate. Expand
Effects of anaerobic regulatory mutations and catabolite repression on regulation of hydrogen metabolism and hydrogenase isoenzyme composition in Salmonella typhimurium
TLDR
The pattern of anaerobic control of hydrogenase activities illustrated the functional diversity of the isoenzymes and, in addition, the physiological distinction between the twoAnaerobic regulatory pathways, anaerilic respiratory genes being fnr dependent and enzymes required during fermentative growth being oxrC dependent. Expand
Fnr, NarP, and NarL regulation of Escherichia coli K-12 napF (periplasmic nitrate reductase) operon transcription in vitro.
TLDR
In vitro transcription experiments demonstrate that, in the presence of Fnr, the NarP protein causes efficient transcription activation whereas the NarL protein does not, which suggests that Fnr and NarP may act synergistically to activate napF operon expression. Expand
Characterization of divergent NtrA‐dependent promoters in the anaerobically expressed gene cluster coding for hydrogenase 3 components of Escherichia coli
TLDR
The regulatory region of two divergently oriented transcriptional units involved in the formation of the gas‐evolving hydrogenase (isoenzyme 3) of Escherichia coli was investigated and it was shown that transcription of both promoters was NtrA‐dependent and that it was regulated in an identical manner. Expand
Role of the transcriptional activator AppY in regulation of the cyx appA operon of Escherichia coli by anaerobiosis, phosphate starvation, and growth phase
TLDR
The possibility that AppY is a third global regulator of energy metabolism genes is discussed, and the product of the previously identified appY gene, which when present on a high-copy-number plasmid stimulates synthesis of acid phosphatase, was shown to activate the cyx promoter. Expand
The oxygen‐responsive transcriptional regulator FNR of Escherichia coli : the search for signals and reactions
TLDR
The rationale for regulation of alternative metabolic pathways by FNR and other oxygen‐dependent regulators is discussed and only the terminal reductases of respiration, and not the dehydrogenases, are regulated in such a way as to achieve maximal H+/e− ratios and ATP yields. Expand
Mutational analysis of the operon (hyc) determining hydrogenase 3 formation in Escherichia coli
TLDR
A model is proposed for the functional interaction of the different hyc operon gene products in the formate hydrogenlyase complex, which is based on the results of the mutational analysis, on the determination of the subcellular localization of the FdhF, HyCE, HycF and HycG polypeptides and on the similarity of hyc gene product sequences with those from other hydrogenase systems. Expand
...
1
2
3
4
5
...