Glutathione reductase

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Docosahexaenoic acid enhances the antioxidant response of human fibroblasts by upregulating γ-glutamyl-cysteinyl ligase and glutathione reductase

Docosahexaenoic acid enhances the antioxidant response of human fibroblasts by upregulating γ-glutamyl-cysteinyl ligase and glutathione reductase

Fig. 6. Correlation between GSH content and glutathione reductase (GR) activity for twenty-eight cell samples of the time course study. Pearson r ¼ 0·9883, P, 0·0001; dashed lines indicate 2 95 % CI. Fig. 7. Antioxidant responsive element (ARE) consensus sequences (GTGACNNNGC, black box) identified in 5 0 distal regions of glutathione reductase (GR) and four other genes used for comparison (HO-1, haem oxygenase I; GCLR, regularory subunit of g-glutamyl-cysteinyl ligase; GSTA3, glutathione S-transferase A3; NQO1, NADPH quinine oxidoreductase I). Positions were calculated from the initial exon start. Gene references were: GR:jNT_007995.14jHs8_8152:841462- 910498; HO1:jNT_011520.10jHs22_11677:15127825-15190594; GCLR: jNT_007592.14jHs6_7749:44194601-44323831; GSTA3:jNT_007592.14jHs6_7749: 43677940-43831413; NQO1:jNT_010498.15jHs16_10655:23344695-23387404.
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Arabidopsis glutathione reductase 2 is indispensable in plastids, while mitochondrial glutathione is safeguarded by additional reduction and transport systems

Arabidopsis glutathione reductase 2 is indispensable in plastids, while mitochondrial glutathione is safeguarded by additional reduction and transport systems

(Meyer, 2008). Upon oxidation, two molecules of GSH convert to glutathione disulfide (GSSG). In the cytosol, mitochondria and plastids the glutathione redox potential (E GSH ) is highly reduced with only nanomolar concentrations of GSSG present under non- stress conditions (Meyer et al., 2007; Schwarzl€ander et al., 2008). Such a high GSH/GSSG ratio is believed to be maintained by NADPH-dependent glutathione reductases (GRs). In contrast with bacteria, animals and yeast, plant genomes encode two GRs (Xu et al., 2013). In Arabidopsis, GR1 is present in the cytosol, the nucleus and peroxisomes (Reumann et al., 2007; Marty et al., 2009; Delorme-Hinoux et al., 2016). The second isoform, GR2, is dual-targeted to mitochondria and plastids (Creissen et al., 1995; Chew et al., 2003), as supported by proteomics analyses of purified organelles (Ito et al., 2006; Peltier et al., 2006). However, Yu et al. (2013) found no evidence for mitochondrial targeting of full-length GR2YFP constructs and concluded exclusive plas- tidic localisation. While we found that Arabidopsis mutants lack- ing cytosolic GR1 are fully viable (Marty et al., 2009), a deletion mutant lacking functional GR2 is embryo lethal (Tzafrir et al., 2004; Bryant et al., 2011; Ding et al., 2016b). These observations raise important questions about the exact localisation of GR2, the cause of lethality in gr2 mutants, and about the mechanisms main- taining a highly negative glutathione redox potential (E GSH ) in
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Delayed cardiomyopathy in dystrophin deficient mdx mice relies on intrinsic glutathione resource.: Glutathione resource in mdx mice

Delayed cardiomyopathy in dystrophin deficient mdx mice relies on intrinsic glutathione resource.: Glutathione resource in mdx mice

characterize several human inflammatory chronic diseases. 24, 25 Thus, fibroblasts from DMD patients show a low capacity for glutathione synthesis. 26 In contrast, a noticeable feature of mdx mice dystrophic muscles is the up-regulation of glutathione peroxidase and glutathione reductase, which respectively utilizes and recycles reduced glutathione. 27 However, this protective mechanism does not entirely compensate the chronic oxidative challenge since glutathione level in 6-8-week-old mdx mice tibialis anterior muscles is decreased by 20% compared to control mice. 27 Accordingly, green tea polyphenols, which beyond their inherent antioxidant properties promote glutathione synthesis, reduce muscle damage and necrosis in mdx mice. 16, 17 This does not rule out that the intrinsic increased turnover of glutathione in
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Role of Quinone Reductase 2 in the Antimalarial Properties of Indolone-Type Derivatives

Role of Quinone Reductase 2 in the Antimalarial Properties of Indolone-Type Derivatives

The metabolization of these active compounds by RBCs gave rise to EPR spectra with various intensities (Figure 4A). We observed four main peaks characteristic of the [DMPO-OH] • adduct, which originated from the decomposition of the [DMPO-OOH] • formed by trapping superoxide radicals. We also detected smaller amounts of hydroxyl radicals that were converted into methyl radicals by reacting with DMSO (Figure 4A). The amounts of radicals produced by RBCs treated with different compounds are illustrated in Figure 4B. Addition of 20 µM of the hQR2 inhibitor, S29434 before addition of an antimalarial compound caused a reduction of 30 to 50% in the EPR signal intensity. This demonstrated the significant role played by the hQR2 protein in RBCs in reducing the pseudo-quinones, and the subsequent radicals produced when the compound was re-oxidized. It should be noted that other flavoenzymes, as glutathione reductase could reduce the INOD derivatives [26–28]. To confirm that hQR2 could be involved in the antimalarial properties of these compounds, we performed western blot analyses to measure hQR2 expression in healthy and parasitized RBCs (Figure 4C). The results showed that P. falciparum did not affect the hQR2 expression pattern, because hQR2 was expressed in both control and infected RBCs. The same experiments were then performed in Chinese hamster ovary (CHO cells), which permitted modulation of hQR2 expression. We monitored the generation of oxygen radicals in the extracellular medium of CHO cells that overexpressed hQR2 (CHO-QR2) and compared the findings with results obtained with CHO cells that were not transfected with the hQR2 construct (CHO-NT). Similar to our findings in RBCs, the metabolized compounds gave rise to EPR spectra generated by the trapping of superoxide radicals (not shown). The amounts of radicals produced from cells treated with the different compounds are shown in Figure 5.
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Crystal Structure of ChrR—A Quinone Reductase with the Capacity to Reduce Chromate

Crystal Structure of ChrR—A Quinone Reductase with the Capacity to Reduce Chromate

Chromate [Cr(VI)] and other soluble forms of heavy metals and radionuclides are serious environmental pollutants in many hazardous environments, including the U.S. Department of Energy waste sites and corresponding facilities worldwide [1]. The use of Shewanella and Geobacter bacteria has been intensely studied as a potential cost effective solution to this problem. These bacteria can convert the soluble form of many such contaminants, e.g., Cr(VI) and uranyl [U(VI)], to their insoluble valence state of Cr(III) and U(IV), thus making it possible to prevent their spread. While unique features of the membrane-bound electron transport chain enable these bacteria to mediate the dissimilatory reductions [2,3], we showed that nearly all bacteria possess an additional means of chromate reduction, involving soluble enzymes [4,5,6]. However, the effectiveness of bacteria utilizing either mechanism to reduce chromate is hampered because of its toxicity [4,5,7,8]. The latter arises mainly due to the fact that many bacterial metabolic enzymes, e.g., glutathione reductase and lipoyl dehy- drogenase, can vicariously reduce chromate and do so by one electron reduction [4,5,8]. This generates the highly reactive Cr(V) radical, which redox cycles. In this process, Cr(V) is oxidized back to Cr(VI), giving its electron to dioxygen and generating reactive oxygen species (ROS). Repetition of this process results in the generation of large quantities of ROS, which poison the cells due
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Dietary protein and the prevention of glycemic dysregulation: effects of glutathione and cysteine intake

Dietary protein and the prevention of glycemic dysregulation: effects of glutathione and cysteine intake

HS a ) and fed the corresponding diets for 5 weeks. After 4 weeks, blood samples were withdrawn twice at baseline (t=-15 and t=0 min) and at the indicated time after the meal to determine blood postprandial glucose, insulin, GSH and amino acids. Analytical procedures. Unless specified otherwise, all chemicals were obtained from Sigma (France). Blood samples were dropped into prechilled tubes containing 0.7% EDTA and 0.014% aprotinin and the resulting plasma was stored at -20°C. Glucose concentrations were measured using a Glucometer (Roche Diagnostics, France). Insulin was detected by a solid phase two-site enzyme immunoassay (Mercodia Rat Insulin ELISA, Biovalley, France). The insulin sensitivity index (ISI) was calculated as follows [24]: 2/[(Insp •Glyp)+1] ∗ . Amino acid concentrations were determined by HPLC with postcolumn ninhydrin derivatization (Biotek Instruments), as previously described [25]. Protein carbonyl concentrations were measured using a spectrophotometric assay described by Levine [26]. Oxidized (GSSG) and total GSH concentrations were measured using the enzymatic recycling method described by Anderson [27]. Briefly, blood and tissue samples were deproteinized at 4°C using 5 % trichloracetic acid immediately after collection and glutathione assay occurred within four hours following sample preparation, in order to minimize glutathione auto-oxidation. The rate of 5-thio-2-nitrobenzoic acid production from 5,5’-dithiobis-2-nitrobenzoic acid in the presence of glutathione reductase and NADPH was monitored spectrophotometrically at 405 nm and was proportional to the concentration of total GSH in the sample. To determine GSSG concentration, reduced GSH was first derivatized with 2-vinyl-pyridine at slightly acidic pH. The reduction potential of the GSSG/2GSH half-cell (GSH Ehc), an indicator of intracellular redox status, was calculated using the following formula [13]: GSH Ehc (mV) = -264- (59.1/2) ¯log (GSH²/GSSG). We also quantified glycated hemoglobin (HbA1c, BioSystems, Biocade, France), triglycerides (Triglycérides, Biomérieux, France) and free fatty acids (NEFA-C, Wako, Oxoid, France) using biochemical kits. The plasma oxygen radical absorbent capacity (ORAC) was determined using a fluorimetric assay [28]. Liver glutamate-cysteine ligase (GCL) and erythrocyte GSH-peroxidase activities were assessed according to the methods described by White [29] and Paglia [30], respectively.
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Glutathione: Antioxidant Properties Dedicated to Nanotechnologies

Glutathione: Antioxidant Properties Dedicated to Nanotechnologies

7. Conclusions Since its discovery, GSH has been shown to play ubiquitous roles in most living cells, from prokaryotic to eukaryotic organisms. GSH was defined as the intracellular redox buffer, and its major function, either free or associated to proteins, is tightly connected to redox reactions, mainly acting as a reductant versus oxygen and its derived reactive species. From physico-chemical and biochemical points of view, GSH redox properties are well defined and act in cell signaling through post-translational modifications. Disturbance of redox homeostasis related to the depletion of GSH has been shown more and more to be implicated in many pathophysiological states, opening a means for its use as a drug. Glutathione has clearly penetrated fields other than biology, such as therapeutics, with associated nanotechnology approaches for improving its bioavailability and targeting ability. Indeed, growing research considers GSH not only as a drug, but also as a tool for stimuli responsive in drug delivery systems.
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A Chemically Competent Thiosulfuranyl Radical on the Escherichia coli Class III Ribonucleotide Reductase

A Chemically Competent Thiosulfuranyl Radical on the Escherichia coli Class III Ribonucleotide Reductase

cysteine, [ ε- 2 H]-methionine and [ β,γ- 2 H]-methionine, in combination with EPR spectroscopy of the new radical, identi fies this species as a thiosulfuranyl radical (Figure 1C, 8), ge[r]

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Functionalized Glutathione on Chitosan-Genipin Cross-Linked Beads Used for the Removal of Trace Metals from Water

Functionalized Glutathione on Chitosan-Genipin Cross-Linked Beads Used for the Removal of Trace Metals from Water

Copyright © 2020 Samira R. Akaji and David Dewez. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Functionalized glutathione on chitosan-genipin cross-linked beads (CS-GG) was synthesized and tested as an adsorbent for the removal of Fe(II) and Cu(II) from aqueous solution. The beads were characterized by several techniques, including Fourier- transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), CNS elementary analysis, scanning electron mi- croscopy (SEM), and atomic force microscopy (AFM). The effect of several parameters such as the pH, the temperature, and the contact time was tested to optimize the condition for the adsorption reaction. The beads were incubated in aqueous solutions contaminated with different concentrations of Fe(II) and Cu(II) (under the range concentration from 10 to 400 mg·L −1 ), and the adsorption capacity was evaluated by inductively coupled plasma optical emission spectrometry (ICP-OES). The adsorption equilibrium was reached after 120 min of incubation under optimal pH 5 for Fe(II) and after 180 min under optimal pH 6 for Cu(II). According to the Langmuir isotherm, the maximum adsorption capacities (q max ) for Fe(II) and Cu(II) were 208 mg·g −1 and 217 mg·g −1 , respectively. Our results showed that the adsorption efficiency of both metals on CS-GG beads was correlated with the degree of temperature. In addition, the adsorption reaction was spontaneous and endothermic, indicated by the positive values of ΔG 0 and ΔH 0 . Therefore, the present study demonstrated that the new synthesized CS-GG beads had a strong adsorption capacity for Fe(II) and Cu(II) and were efficient to remove these trace metals from aqueous solution.
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Purification and characterization of glutathione S-transferases from two syrphid flies (Syrphus ribesii and Myathropa florae).

Purification and characterization of glutathione S-transferases from two syrphid flies (Syrphus ribesii and Myathropa florae).

nous or xenobiotic hydrophobic molecules (Boy- land and Chasseaud, 1969 ). When conjugated to reduced glutathione (GSH) potentially toxic sub- stances become more water soluble and generally less toxic (Grant and Matsumura, 1989). GSTs are important in insecticide resistance and are involved in the metabolism of organophosphorous and

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Deciphering Radical Transport in the Large Subunit of Class I Ribonucleotide Reductase

Deciphering Radical Transport in the Large Subunit of Class I Ribonucleotide Reductase

peptide corresponding to the C-terminus of the β protein (βC19) of Escherichia coli ribonucleotide reductase (RNR) allows for the temporal monitoring of radical transport into the α2 subunit of RNR. Injection of the photogenerated F 3 Y radical from the [Re]–F 3 Y–βC19 peptide into the surface accessible Y731 of the α2 subunit is only possible when the second Y730 is present. With the Y–Y established, radical transport occurs with a rate constant of 3 × 10 5 s −1 . Point mutations that disrupt the Y–Y dyad shut down radical transport. The ability to obviate radical transport by disrupting the hydrogen bonding network of the amino acids composing the co-linear proton- coupled electron transfer pathway in α2 suggests a finely tuned evolutionary adaptation of RNR to control the transport of radicals in this enzyme.
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Bacillus Subtilis Class Ib Ribonucleotide Reductase: High Activity and Dynamic Subunit Interactions

Bacillus Subtilis Class Ib Ribonucleotide Reductase: High Activity and Dynamic Subunit Interactions

We used the B. anthracis genes 25 as queries of the B. subtilis genome and identi fied six thioredoxin-like proteins (TrxA, Ydbp, YtpP, YdfQ, YusE, and YusI), one thioredoxin reductase (TrxB), and two glutaredoxin-like proteins (YosR and BdbA). TrxA and TrxB are homologues of B. anthracis Trx1 (75% identity) and TR1 (87% identity), suggesting they likely function as the reducing system for the B. subtilis RNR. In addition, previous gene knock-out experiments of all of these proteins and the growth of the resulting deletion mutants in rich or minimal medium revealed that only TrxA and TrxB are essential. 10,56 Using these puri fied proteins, we established that endogenous reductants e ffect a ∼10-fold increase on RNR activity relative to DTT (Table 1) in contrast with the B. anthracis RNR. 25 We also note that we have observed a 20-fold di fference between endogenous reductant and DTT with the S. sanguinis class Ib RNR. 53
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Reduction of Protein Bound Methionine Sulfoxide by a Periplasmic Dimethyl Sulfoxide Reductase

Reduction of Protein Bound Methionine Sulfoxide by a Periplasmic Dimethyl Sulfoxide Reductase

The MsrA, MsrB, and MsrP are the only enzymes for which the ability to reduced MetO in oxidized protein was experimentally demonstrated [ 9 , 10 , 19 , 20 ]. On the contrary, biochemical assays demonstrated that neither the fRMsr, BisC, nor TorZ/MtsZ can catalyze the reduction of MetO in proteins [ 15 , 16 , 32 , 33 ]. The capacity of DMSO reductases to reduce protein bound MetO was not previously evaluated. However, the use of a molecule mimicking a MetO in a peptidic environment suggested that E. coli DmsA might reduce oxidized proteins and protect periplasmic proteins from oxidation [ 30 ]. But, previous comparisons of Msr activity using oxidized proteins or molecules mimicking peptide bound MetO as substrates revealed that such molecules might not be appropriate model substrates to decipher whether a MetO reductase can or cannot efficiently act on oxidized protein [ 14 ]. In this work, we evaluated the capacity of the R. sphaeroides DorA DMSO reductase to reduce model oxidized proteins and MetO-containing peptides, and compared it to its ability to reduce DMSO and the free L-Met-R,S-O. The first oxidized protein tested was the bovine β-casein, an intrinsically disordered protein possessing 6 Met oxidizable as either Met-R-O or Met-S-O upon reaction with hydrogen peroxide and previously used for the characterization of several Msr enzymes [ 14 , 20 ]. We also showed that DorA can reduce MetO in two R. sphaeroides periplasmic proteins, TakP and PCu A C, both potentially exposed to oxidative conditions in the bacteria. TakP is a soluble α-keto
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2,4-dienoyl-CoA reductase regulates lipid homeostasis in treatment-resistant prostate cancer.

2,4-dienoyl-CoA reductase regulates lipid homeostasis in treatment-resistant prostate cancer.

In this study, we use a combination of proteomics and meta- bolomics to perform an unbiased characterisation of LNCaP- derived cell lines chronically exposed to long-term bicalutamide, apalutamide or enzalutamide treatment. We show that long-term resistance to AR inhibition is sustained by profound changes in glucose and lipid metabolism. This metabolic rearrangement is mainly dependent on aberrant AR signalling. In addition, we identify a protein signature associated with acquired resistance to ARI. Among the top candidates, 2,4-dienoyl-CoA reductase (DECR1), a mitochondrial enzyme involved in polyunsaturated fatty acid (PUFA) degradation, represents a potential therapeutic target for CRPC. DECR1 deletion in CRPC cells reduces in vitro proliferation and impairs CRPC tumour growth. Mechanistically, we show that DECR1-deficient prostate cancer cells accumulate higher levels of polyunsaturated lipids. This results in a strong ER stress response and an increased sensitivity to GPX4 inhibition, and suggests a potential role for DECR1 in the control of redox homeostasis.
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Phthalates modulate steroid 5-reductase transcripts in the Western clawed frog embryo.

Phthalates modulate steroid 5-reductase transcripts in the Western clawed frog embryo.

Table 3 Effects of di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), and diethyl phthalate (DEP). 589[r]

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The class III ribonucleotide reductase from Neisseria bacilliformis can utilize thioredoxin as a reductant

The class III ribonucleotide reductase from Neisseria bacilliformis can utilize thioredoxin as a reductant

Departments of a Chemistry and b Biology, and c Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139 Contributed by JoAnne Stubbe, July 29, 2014 (sent for review July 13, 2014) The class III anaerobic ribonucleotide reductases (RNRs) studied to date couple the reduction of ribonucleotides to deoxynucleotides with the oxidation of formate to CO 2 . Here we report the cloning and heterologous expression of the Neisseria bacilliformis class III RNR and show that it can catalyze nucleotide reduction using the ubiquitous thioredoxin/thioredoxin reductase/NADPH system. We present a structural model based on a crystal structure of the ho- mologous Thermotoga maritima class III RNR, showing its architec- ture and the position of conserved residues in the active site. Phylogenetic studies suggest that this form of class III RNR is pres- ent in bacteria and archaea that carry out diverse types of anaer- obic metabolism.
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Allosteric Inhibition of Human Ribonucleotide Reductase by dATP Entails the Stabilization of a Hexamer

Allosteric Inhibition of Human Ribonucleotide Reductase by dATP Entails the Stabilization of a Hexamer

Activity in the Presence of dATP and ATP. In an e ffort to correlate oligomerization with the specific activity of α, dCDP formation was measured as a function of dATP and ATP in the presence of 4 μM α, a 5-fold excess of β, 0.5 mM [5- 3 H]- CDP, human thioredoxin, and human thioredoxin reductase. To prevent precipitation of the subunits at these high concentrations, the assay bu ffer was modified with the addition of 150 mM KCl. In the absence of dATP or ATP, we find that turnover occurs at a very low rate of 0.080 ± 0.014 s −1 (initial points in Figure 2 C,F). Titration of dATP leads to a 3.2-fold increase up to 4 μM dATP (equimolar with α), followed by a steady decrease to 0.045 ± 0.007 s −1 at 16 μM dATP ( Figure 2 C). On the basis of previously reported dissociation constants of 0.07 and 1.5 μM for dATP binding to the specificity and activity sites, respectively, in murine RNR, 40 our observation of biphasic behavior in activity can be attributed to dATP first binding the speci ficity site, which stimulates CDP reduction, followed by dATP binding to the activity-regulating site causing inhibition. In contrast, titration of ATP leads to a steady increase in turnover up to 3 mM ATP ( Figure 2 F), and then maintenance of this high level of activity out to 10 mM ATP ( Figure S7 ), the maximum concentration of ATP we tested. This trend in activity data is as expected from a positive e ffector and is consistent with recent work on murine RNR. 16
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An active dimanganese(III)-tyrosyl radical cofactor in Escherichia coli class Ib ribonucleotide reductase

An active dimanganese(III)-tyrosyl radical cofactor in Escherichia coli class Ib ribonucleotide reductase

1Abbreviations: α2, ribonucleotide reductase large subunit; β2, ribonucleotide reductase small subunit; Ba, Bacillus anthracis; Ca, Corynebacterium ammoniagenes; CDP, cytidine 5′-diphosphate; CV, column volumes; dATP, deoxyadenosine 5′-triphosphate; DEPMPO, 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline N-oxide; dNTP, deoxynucleoside 5′-triphosphate; Ec, Escherichia coli; EDTA, ethylenediaminetetraacetic acid; GR536, E. coli strain with deletions in the five known iron uptake pathways; HU, hydroxyurea; met-NrdF, tyrosyl radical-reduced diferric NrdF; Mt, Mycobacterium tuberculosis; N•, nitrogen-centered radical; N3CDP, 2′-azido-2′-deoxycytidine 5′-diphosphate; Ni-NTA, nickel nitrilotriacetic acid; NrdIhq, NrdI hydroquinone form; NrdIox, oxidized NrdI; NrdIsq, NrdI semiquinone form; RNR, ribonucleotide reductase; SA, specific activity; SDS-PAGE, sodium dodecyl sulfate–polyacrylamide gel electrophoresis; SOD, superoxide dismutase; St, Salmonella typhimurium; W+•, tryptophan cation radical; Y•, tyrosyl radical
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Biochemical Function, Molecular Structure and Evolution of an Atypical Thioredoxin Reductase from Desulfovibrio vulgaris

Biochemical Function, Molecular Structure and Evolution of an Atypical Thioredoxin Reductase from Desulfovibrio vulgaris

( Obiero and Sanders, 2011 ). On the contrary, the residues implicated in NAD(P)H-binding are partially or fully absent. However, in the 2’P group-binding region, only few residues are well conserved among TRi proteins with a TQ/NGK motif instead of the HRRD motif. Like in DvH, we can hypothesize that in SRBs and Firmicutes which contain TR1 and TRi homologs, the substitutions selected during the evolutionary history of TRi excluded NAD(P)H as substrate and therefore improved the capacities of the Trx system. As three thermophilic cellulolytic clostridia harbor only TRi homologs, this enzyme must play the essential role of the Trx system and we can postulate that in these Clostridium species the electron donor is the same as the one of DvTRi. Evolutionary studies showed that TRi, TR1, dcTR1 and TR3 underwent a complex evolutionary history (with TR1 as a common gene ancestor in Archaea and Bacteria). These were affected by both gene duplications and horizontal gene transfer events, leading to the appearance of TR3/dcTR1 and TRi through subfunctionalization over the evolutionary time. A recent in silico identification of deazaflavin-dependent flavin- containing thioredoxin reductase (DFTR) homologs (e.g., Mj- DFTR, from Methanocaldococcus jannaschii, Susanti et al., 2016 ) within nr database showed that these proteins were limited to the deeply-rooted methanogens (in Euryarchaeota phylum), therefore suggesting that these atypical TRs (TRi, TR3, dcTR1 and Mj-DFTR) are only found in particular taxonomic clades and should be useful in specific environmental niches. Multiple alignment of DvTRi with non-NADPH dependent TRs shows that there is a high variability in the region corresponding to the 2 0
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The function of the Saccharomyces Cerevisiae ribonucleotide reductase second [beta] subunit in DNA repair

The function of the Saccharomyces Cerevisiae ribonucleotide reductase second [beta] subunit in DNA repair

62.. In conclusion, strains rnr4A mutant display extreme resistance to 4-NQO induced DNA damage cornpared with the parent; this DNA damage is neither a “UV mimetic DNA damage which is pr[r]

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