scholarly journals Interplay of cellular cAMP levels, σ S activity and oxidative stress resistance in Escherichia coli

Microbiology ◽  
2009 ◽  
Vol 155 (5) ◽  
pp. 1680-1689 ◽  
Author(s):  
Evelyn Barth ◽  
Katherine V. Gora ◽  
Katharina M. Gebendorfer ◽  
Florian Settele ◽  
Ursula Jakob ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Escherichia Coli ◽  
Stress Resistance ◽  
Mutational Analysis ◽  
Receptor Protein ◽  
Mammalian Host ◽  
Oxidative Stress Resistance ◽  
E Coli ◽  
Camp Levels ◽  
And Oxidative Stress

Hypochlorous acid (HOCl), the active ingredient of household bleach, functions as a powerful antimicrobial that is used not only in numerous industrial applications but also in mammalian host defence. Here we show that multicopy expression of cpdA, encoding the cAMP phosphodiesterase, leads to a dramatically increased resistance of Escherichia coli to HOCl stress as well as to the unrelated hydrogen peroxide (H2O2) stress. This general oxidative stress resistance is apparently caused by the CpdA-mediated decrease in cellular cAMP levels, which leads to the partial inactivation of the global transcriptional regulator cAMP receptor protein (CRP). Downregulation of CRP in turn causes the derepression of rpoS, encoding the alternative sigma factor σ S, which activates the general stress response in E. coli. We found that these highly oxidative stress-resistant cells have a substantially increased capacity to combat HOCl-mediated insults and to degrade reactive oxygen species. Mutational analysis revealed that the DNA-protecting protein Dps, the catalase KatE, and the exonuclease III XthA play the predominant roles in conferring the high resistance of rpoS-overexpressing strains towards HOCl and H2O2 stress. Our results demonstrate the close regulatory interplay between cellular cAMP levels, σ S activity and oxidative stress resistance in E. coli.

Functional characterization of a mycothiol peroxidase in Corynebacterium glutamicum that uses both mycoredoxin and thioredoxin reducing systems in the response to oxidative stress

2015 ◽  
Vol 469 (1) ◽  
pp. 45-57 ◽  
Author(s):  
Meiru Si ◽  
Yixiang Xu ◽  
Tietao Wang ◽  
Mingxiu Long ◽  
Wei Ding ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Corynebacterium Glutamicum ◽  
Stress Resistance ◽  
Functional Characterization ◽  
Gram Positive ◽  
Oxidative Stress Resistance ◽  
Proton Donors ◽  
New Type ◽  
And Oxidative Stress

Mycothiol peroxidase, a new type of GSH peroxidase distributed in GSH-lacking high-(G+C)-content Gram-positive actinobacteria, uses both mycoredoxin and thioredoxin systems as proton donors for regeneration and oxidative stress resistance.

Anr, the anaerobic global regulator, modulates the redox state and oxidative stress resistance in Pseudomonas extremaustralis

Microbiology ◽  
2013 ◽  
Vol 159 (Pt_2) ◽  
pp. 259-268 ◽  
Author(s):  
Paula M. Tribelli ◽  
Pablo I. Nikel ◽  
Oscar J. Oppezzo ◽  
Nancy I. López
Keyword(s):  
Oxidative Stress ◽  
Stress Resistance ◽  
Redox State ◽  
Global Regulator ◽  
Oxidative Stress Resistance ◽  
Pseudomonas Extremaustralis ◽  
And Oxidative Stress

scholarly journals Cyanobacterial Mn-catalase ‘KatB’: Molecular link between salinity and oxidative stress resistance

2016 ◽  
Vol 9 (5) ◽  
pp. e1216738 ◽  
Author(s):  
Dhiman Chakravarty ◽  
Manisha Banerjee ◽  
Namrata Waghmare ◽  
Anand Ballal
Keyword(s):  
Oxidative Stress ◽  
Stress Resistance ◽  
Oxidative Stress Resistance ◽  
And Oxidative Stress

scholarly journals Proline Metabolism IncreaseskatGExpression and Oxidative Stress Resistance in Escherichia coli

2014 ◽  
Vol 197 (3) ◽  
pp. 431-440 ◽  
Author(s):  
Lu Zhang ◽  
James R. Alfano ◽  
Donald F. Becker
Keyword(s):  
Oxidative Stress ◽  
Escherichia Coli ◽  
Hydrogen Peroxide ◽  
Mutant Strain ◽  
Stress Resistance ◽  
Proline Metabolism ◽  
Wild Type ◽  
Content Type ◽  
Oxidative Stress Resistance ◽  
Proline Utilization

The oxidation ofl-proline to glutamate in Gram-negative bacteria is catalyzed by the proline utilization A (PutA) flavoenzyme, which contains proline dehydrogenase (PRODH) and Δ1-pyrroline-5-carboxylate (P5C) dehydrogenase domains in a single polypeptide. Previous studies have suggested that aside from providing energy, proline metabolism influences oxidative stress resistance in different organisms. To explore this potential role and the mechanism, we characterized the oxidative stress resistance of wild-type andputAmutant strains ofEscherichia coli. Initial stress assays revealed that theputAmutant strain was significantly more sensitive to oxidative stress than the parental wild-type strain. Expression of PutA in theputAmutant strain restored oxidative stress resistance, confirming that depletion of PutA was responsible for the oxidative stress phenotype. Treatment of wild-type cells with proline significantly increased hydroperoxidase I (encoded bykatG) expression and activity. Furthermore, the ΔkatGstrain failed to respond to proline, indicating a critical role for hydroperoxidase I in the mechanism of proline protection. The global regulator OxyR activates the expression ofkatGalong with several other genes involved in oxidative stress defense. In addition tokatG, proline increased the expression ofgrxA(glutaredoxin 1) andtrxC(thioredoxin 2) of the OxyR regulon, implicating OxyR in proline protection. Proline oxidative metabolism was shown to generate hydrogen peroxide, indicating that proline increases oxidative stress tolerance inE. colivia a preadaptive effect involving endogenous hydrogen peroxide production and enhanced catalase-peroxidase activity.

scholarly journals Enhanced Nox1 expression and oxidative stress resistance in c-kit-positive hematopoietic stem/progenitor cells

2014 ◽  
Vol 454 (3) ◽  
pp. 376-380 ◽  
Author(s):  
Yoshishige Urata ◽  
Shinji Goto ◽  
Lan Luo ◽  
Hanako Doi ◽  
Yuriko Kitajima ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Progenitor Cells ◽  
Stress Resistance ◽  
Hematopoietic Stem ◽  
Oxidative Stress Resistance ◽  
And Oxidative Stress

scholarly journals Manganese regulation of virulence factors and oxidative stress resistance in Neisseria gonorrhoeae

2010 ◽  
Vol 73 (5) ◽  
pp. 899-916 ◽  
Author(s):  
Hsing-Ju Wu ◽  
Kate L. Seib ◽  
Yogitha N. Srikhanta ◽  
Jennifer Edwards ◽  
Stephen P. Kidd ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Neisseria Gonorrhoeae ◽  
Virulence Factors ◽  
Stress Resistance ◽  
Oxidative Stress Resistance ◽  
And Oxidative Stress ◽  
Manganese Regulation
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