scholarly journals yqhG Contributes to Oxidative Stress Resistance and Virulence of Uropathogenic Escherichia coli and Identification of Other Genes Altering Expression of Type 1 Fimbriae

2019 ◽  
Vol 9 ◽  
Author(s):  
Hicham Bessaiah ◽  
Pravil Pokharel ◽  
Hajer Habouria ◽  
Sébastien Houle ◽  
Charles M. Dozois
Keyword(s):  
Oxidative Stress ◽  
Escherichia Coli ◽  
Stress Resistance ◽  
Uropathogenic Escherichia Coli ◽  
Oxidative Stress Resistance ◽  
Type 1 Fimbriae

scholarly journals Uropathogenic Escherichia coli P and Type 1 Fimbriae Act in Synergy in a Living Host to Facilitate Renal Colonization Leading to Nephron Obstruction

2011 ◽  
Vol 7 (2) ◽  
pp. e1001298 ◽  
Author(s):  
Keira Melican ◽  
Ruben M. Sandoval ◽  
Abdul Kader ◽  
Lina Josefsson ◽  
George A. Tanner ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Uropathogenic Escherichia Coli ◽  
Type 1 Fimbriae

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 Type 1 Fimbriae, a Colonization Factor of Uropathogenic Escherichia coli, Are Controlled by the Metabolic Sensor CRP-cAMP

2009 ◽  
Vol 5 (2) ◽  
pp. e1000303 ◽  
Author(s):  
Claudia M. Müller ◽  
Anna Åberg ◽  
Jurate Straseviçiene ◽  
Levente Emődy ◽  
Bernt Eric Uhlin ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Uropathogenic Escherichia Coli ◽  
Type 1 Fimbriae ◽  
Colonization Factor ◽  
Metabolic Sensor

scholarly journals Differential Roles of the Universal Stress Proteins of Escherichia coli in Oxidative Stress Resistance, Adhesion, and Motility

2005 ◽  
Vol 187 (18) ◽  
pp. 6265-6272 ◽  
Author(s):  
Laurence Nachin ◽  
Ulf Nannmark ◽  
Thomas Nyström
Keyword(s):  
Oxidative Stress ◽  
Escherichia Coli ◽  
Stress Resistance ◽  
Stress Proteins ◽  
Stress Protein ◽  
Physiological Role ◽  
Cellular Growth ◽  
Yeast Cells ◽  
Phenotypic Characterization ◽  
Oxidative Stress Resistance

ABSTRACT The universal stress protein (UspA) superfamily encompasses a conserved group of proteins that are found in bacteria, archaea, and eukaryotes. Escherichia coli harbors six usp genes—uspA, -C, -D, -E, -F, and -G—the expression of which is triggered by a large variety of environmental insults. The uspA gene is important for survival during cellular growth arrest, but the exact physiological role of the Usp proteins is not known. In this work we have performed phenotypic characterization of mutants with deletions of the six different usp genes. We report on hitherto unknown functions of these genes linked to motility, adhesion, and oxidative stress resistance, and we show that usp functions are both overlapping and distinct. Both UspA and UspD are required in the defense against superoxide-generating agents, and UspD appears also important in controlling intracellular levels of iron. In contrast, UspC is not involved in stress resistance or iron metabolism but is essential, like UspE, for cellular motility. Electron microscopy demonstrates that uspC and uspE mutants are devoid of flagella. In addition, the function of the uspC and uspE genes is linked to cell adhesion, measured as FimH-mediated agglutination of yeast cells. While the UspC and UspE proteins promote motility at the expense of adhesion, the UspF and UspG proteins exhibit the exact opposite effects. We suggest that the Usp proteins have evolved different physiological functions that reprogram the cell towards defense and escape during cellular stress.

Source of tryptone in growth medium affects oxidative stress resistance in Escherichia coli

2004 ◽  
Vol 97 (1) ◽  
pp. 124-133 ◽  
Author(s):  
P. De Spiegeleer ◽  
J. Sermon ◽  
A. Lietaert ◽  
A. Aertsen ◽  
C.W. Michiels
Keyword(s):  
Oxidative Stress ◽  
Escherichia Coli ◽  
Growth Medium ◽  
Stress Resistance ◽  
Oxidative Stress Resistance

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.

Distribution of fimH Gene in Local Isolates of Adhesive Uropathogenic Escherichia coli

2019 ◽  
Vol 9 (o3) ◽  
Author(s):  
Omar Abdulkareem Ali ◽  
Ruqayah Qubtan Taha
Keyword(s):  
Escherichia Coli ◽  
Virulence Factors ◽  
Biofilm Formation ◽  
Uropathogenic Escherichia Coli ◽  
Adhesion Assay ◽  
E Coli ◽  
Type 1 Fimbriae ◽  
Formation Type ◽  
Uroepithelial Cells

Adhesion is an influential step for bacterial vigor in clinical micro-environments, type 1 fimbriae are essential virulence factors help uropathogenic E. coli in invasion and colonization of uroepithelial cells, the first step of UTIs and biofilm formation. Type 1 fimbriae of E. coli contain FimH protein at the tip encoding via fimH gene cluster, this study was conducted for determination the fimH gene distribution in uro-pathogenic E. coli isolated from UTIs patients. The results of adhesion assay show that (83.6%) of uropathogenic E. coli were high adherent isolates. While the results of E. coli fimH gene amplification prove that, of all E. coli isolates, the fimH gene was found in (87.1%), while among high adherent isolates it was found in (92.6%), and that Shows the function of type 1 fimbriae in the colonization and infection of urinary tracts in addition to other adhesions virulence agents of uropathogenic E. coli.

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