Tellurite-mediated damage to the Escherichia coli NDH-dehydrogenases and terminal oxidases in aerobic conditions

Díaz-Vásquez, Waldo A.; Abarca-Lagunas, María José; Cornejo, Fabián A.; Pinto, Camilo A.; Arenas, Felipe; Vásquez, Claudio C.

doi:10.1016/j.abb.2014.10.011

Cited by 16 publications

(19 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The nitrate reductases do not appear to be a factor in the current work, as the addition of nitrite or nitrate did not provide any change in MIC of tellurite toxicity and would not have been expected as the experiments here were performed aerobically. In E. coli 6-phosphoguconate dehydrogenase (Sandoval et al, 2015 ) and NDH-II dehydrogenase (Díaz-Vásquez et al, 2014 , 2015 ) appear to have tellurite reduction activity. In these studies, this reduction leads to superoxide production that affects aerobic electron transport chains leading to a move into an anaerobic respiratory state (Molina-Quiroz et al, 2014 ).…”

Section: Discussionmentioning

confidence: 99%

Selenite Protection of Tellurite Toxicity Toward Escherichia coli

Vrionis

Wang

Haslam

et al. 2015

Front. Mol. Biosci.

View full text Add to dashboard Cite

In this work the influence of selenite on metal resistance in Escherichia coli was examined. Both synergistic and antagonistic resistance and toxicities were found upon co exposure with selenite. In wild type cells co-exposure to selenite had little effect on arsenic resistance, decreased resistance to cadmium and mercury but led to a dramatically increased resistance to tellurite of 32-fold. Due to the potential importance of thiol chemistry in metal biochemistry, deletion strains in γ-glutamylcysteine synthetase (key step in glutathione biosynthesis, encoded by gshA), thioredoxin (trxA), glutaredoxin (grxA), glutathione oxidoreductase (gor), and the periplasmic glutathione transporter (cydD) were also evaluated for resistance to various metals in the presence of selenite. The protective effect of selenite on tellurite toxicity was seen in several of the mutants and was pronounced in the gshA mutant were resistance to tellurite was increased up to 1000-fold relative to growth in the absence of selenite. Thiol oxidation studies revealed a faster rate of loss of reduced thiol content in the cell with selenite than with tellurite, indicating differential thiol reactivity. Selenite addition resulted in reactive oxygen species (ROS) production equivalent to levels associated with H2O2 addition. Tellurite addition resulted in considerably lower ROS generation while vanadate and chromate treatment did not increase ROS production above that of background. This work shows increased resistance toward most oxyanions in mutants of thiol redox suggesting that metalloid reaction with thiol components such as glutathione actually enhances toxicity of some metalloids.

show abstract

Section: Discussionmentioning

confidence: 99%

Selenite Protection of Tellurite Toxicity Toward Escherichia coli

Vrionis

Wang

Haslam

et al. 2015

Front. Mol. Biosci.

View full text Add to dashboard Cite

show abstract

“…While ActP is a symporter associated with the Na + gradient, the PitAB system is dependent on the transmembrane proton gradient (Harris et al, 2001). Along this line, it has been recently shown that tellurite affects the E. coli electron transport chain (Díaz-Vásquez et al, 2014b) and hence ATP generation (Lohmeier-Vogel et al, 2004). This would have two important effects on ActP: alteration of the transmembrane Na + gradient and the inhibition of the acs operon, which would cause a decrease in actP expression.…”

Section: Genementioning

confidence: 98%

The ActP acetate transporter acts prior to the PitA phosphate carrier in tellurite uptake by Escherichia coli

Elías

Díaz-Vásquez

Abarca-Lagunas

et al. 2015

Microbiological Research

Self Cite

View full text Add to dashboard Cite

The tellurium oxyanion tellurite is harmful for most microorganisms. Since its toxicity occurs chiefly once the toxicant reaches the intracellular compartment, unveiling the toxicant uptake process is crucial for understanding the whole phenomenon of tellurium toxicity. While the PitA phosphate transporter is thought to be one of the main paths responsible for toxicant entry into Escherichia coli, genetic and physiological evidence have identified the ActP acetate carrier as the main tellurite importer in Rhodobacter capsulatus. In this work, new background on the role of these transporters in tellurite uptake by E. coli is presented. It was found that, similar to what occurs in R. capsulatus, ActP is able to mediate toxicant entry to this bacterium. Lower reactive oxygen species levels were observed in E. coli lacking the actP gene. Antioxidant enzyme catalase and fumarase C activity was almost unchanged after short exposure of E. coli ΔactP to sublethal tellurite concentrations, suggesting a low antioxidant response. In this strain, tellurite uptake decreased significantly during the first 5 min of exposure and inductively coupled plasma optical emission spectroscopy assays using an actP-overexpressing strain confirmed that this carrier mediates toxicant uptake. Relative gene expression experiments by qPCR showed that actP expression is enhanced at short times of tellurite exposure, while pitA and pitB genes are induced later. Summarizing, the results show that ActP is involved in tellurite entry to E. coli and that its participation occurs mainly at early stages of toxicant exposure.

show abstract

“…The previous findings raised the question of the reversibility of the inactivation process. We attempted to restore dehydrogenase activities by adopting a procedure used earlier for the reconstruction of the iron-sulfur clusters in soluble [25] and membrane [7] enzymes. After 60 min anaerobic incubation with mercaptoethanol, Fe 2+ and S 2-, the enzymatic activities of membranes prepared from cells grown with paraquat were found to be increased by approximately 1.4-1.8 fold to levels comparable with those of membranes from paraquat-untreated cells (Figure 1).…”

Section: Resultsmentioning

confidence: 99%

“…The procedure used is a slight modification of previously described protocols [7,25]. A solution was prepared containing 0.1 M NaCl, 0.1 M 2-mercaptoethanol, 0.2 mM Na 2 S and 0.1 M sodium phosphate buffer (pH 7.3) in which membranes were suspended at the final concentration of 0.5 mg protein per mL.…”

Section: Iron Sulfur Clusters Restorationmentioning

confidence: 99%

“…In the isolated rat liver mitochondria, the superoxide generator paraquat induced multiple effects on oxidative phosphorylation, including depression of respiratory activity through partial inhibition at ubiquinol-cytochrome c reductase and cytochrome c oxidase [5]. The breakdown of respiratory electron flow due to ROS attack was identified as the key event in the inactivation of Escherichia coli by UVA irradiation [6] or by tellurite treatment [7].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Modifications of the Aerobic Respiratory Chain of Paracoccus Denitrificans in Response to Superoxide Oxidative Stress

Sedláček

Kučera

2019

Microorganisms

View full text Add to dashboard Cite

Paracoccus denitrificans is a strictly respiring bacterium with a core respiratory chain similar to that of mammalian mitochondria. As such, it continuously produces and has to cope with superoxide and other reactive oxygen species. In this work, the effects of artificially imposed superoxide stress on electron transport were examined. Exposure of aerobically growing cells to paraquat resulted in decreased activities of NADH dehydrogenase, succinate dehydrogenase, and N,N,N’,N’-tetramethyl-p-phenylenediamine (TMPD) oxidase. Concomitantly, the total NAD(H) pool size in cells was approximately halved, but the NADH/NAD+ ratio increased twofold, thus partly compensating for inactivation losses of the dehydrogenase. The inactivation of respiratory dehydrogenases, but not of TMPD oxidase, also took place upon treatment of the membrane fraction with xanthine/xanthine oxidase. The decrease in dehydrogenase activities could be fully rescued by anaerobic incubation of membranes in a mixture containing 2-mercaptoethanol, sulfide and ferrous iron, which suggests iron–sulfur clusters as targets for superoxide. By using cyanide titration, a stress-sensitive contribution to the total TMPD oxidase activity was identified and attributed to the cbb3-type terminal oxidase. This response (measured by both enzymatic activity and mRNA level) was abolished in a mutant defective for the FnrP transcription factor. Therefore, our results provide evidence of oxidative stress perception by FnrP.

show abstract

Tellurite-mediated damage to the Escherichia coli NDH-dehydrogenases and terminal oxidases in aerobic conditions

Cited by 16 publications

References 65 publications

Selenite Protection of Tellurite Toxicity Toward Escherichia coli

Selenite Protection of Tellurite Toxicity Toward Escherichia coli

The ActP acetate transporter acts prior to the PitA phosphate carrier in tellurite uptake by Escherichia coli

Modifications of the Aerobic Respiratory Chain of Paracoccus Denitrificans in Response to Superoxide Oxidative Stress

Contact Info

Product

Resources

About