A5080210877- Redox biology and oxidative stress
- Photosynthetic Processes and Mechanisms
- Plant Stress Responses and Tolerance
- Metal-Catalyzed Oxygenation Mechanisms
- Glutathione Transferases and Polymorphisms
- Trace Elements in Health
- Sulfur Compounds in Biology
- Enzyme Structure and Function
- Heat shock proteins research
- Algal biology and biofuel production
- Plant responses to elevated CO2
- Plant biochemistry and biosynthesis
- Antioxidant Activity and Oxidative Stress
- Genomics, phytochemicals, and oxidative stress
- Seed Germination and Physiology
- Light effects on plants
- Endoplasmic Reticulum Stress and Disease
- Plant Molecular Biology Research
- Microbial Metabolites in Food Biotechnology
- Selenium in Biological Systems
- Cancer Research and Treatments
- Pancreatitis Pathology and Treatment
- Surgical Sutures and Adhesives
- Metalloenzymes and iron-sulfur proteins
- Plant nutrient uptake and metabolism
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2015-2025
Centre National de la Recherche Scientifique
2015-2025
Institut de Biosciences et Biotechnologies
2007-2025
Aix-Marseille Université
2012-2024
Institut de Biosciences et biotechnologies d'Aix-Marseille
2020
Laboratoire de Biologie du Développement
2019
Universidad de Navarra
2018
Universidad de Zaragoza
2018
Ecologie Microbienne Lyon
2012-2016
Hospital Universitario Puerta de Hierro Majadahonda
2014
Vitamin E is considered a major antioxidant in biomembranes, but little evidence exists for this function plants under photooxidative stress. Leaf discs of two vitamin mutants, tocopherol cyclase mutant (vte1) and homogentisate phytyl transferase (vte2), were exposed to high light stress at low temperature, which resulted bleaching lipid photodestruction. However, was not observed whole long-term stress, unless the conditions extreme (very temperature very light), suggesting compensatory...
We provide here an exhaustive overview of the glutathione (GSH) peroxidase (Gpx) family poplar (Populus trichocarpa). Although these proteins were initially defined as GSH dependent, in fact they use only reduced thioredoxin (Trx) for their regeneration and do not react with or glutaredoxin, constituting a fifth class peroxiredoxins. The two chloroplastic Gpxs display marked selectivity toward electron donors, being exclusively specific Trxs y type reduction. In contrast, are much less...
The chloroplastic drought-induced stress protein of 32 kD (CDSP32) is composed two thioredoxin modules and induced by environmental oxidative conditions. We investigated whether the plastidic BAS1, which related to eubacterial 2-Cys peroxiredoxin, a target for CDSP32. Using CDSP32 active-site mutant, we showed that BAS1 proteins form mixed disulfide complex in vitro. Moreover, affinity chromatography indicated major chloroplasts. was able reduce vitro, displayed CDSP32-dependent peroxidase...
ABSTRACT Arabidopsis ( thaliana ) plants were grown in a hydroponic culture system for 7 to 14 d the absence or presence of 75 µ M Cd Cu. The Cu treatment resulted visual leaf symptoms, together with anthocyanin accumulation and loss turgor. Pronounced lipid peroxidation, which was detected by autoluminescence imaging malondialdehyde titration, observed Cu‐treated leaves. also pigments but peroxidation oxidative stress less pronounced than leaves exposed Analysis low‐molecular‐weight...
Seeds are in a natural oxidative context leading to protein oxidation. Although inevitable for proper progression from maturation germination, oxidation at high levels is detrimental and associated with seed aging. Oxidation of methionine sulfoxide common form damage observed during aging all organisms. This reversible through the action reductases (MSRs), which play key roles lifespan control yeast animal cells. To investigate relationship between MSR capacity longevity plant seeds, we...
Two types of methionine (Met) sulfoxide reductases (Msr) catalyze the reduction Met (MetSO) back to Met. MsrA, well characterized in plants, exhibits an activity restricted Met-S-SO-enantiomer. Recently, a new type Msr enzyme, called MsrB, has been identified various organisms and shown catalytically reduce R-enantiomer MetSO. In very little information is available about MsrB we focused our attention on Arabidopsis (Arabidopsis thaliana) proteins. Searching genome databases, have nine open...
Summary Proteins homologous to fibrillin, a pepper plastid lipid‐associated protein involved in carotenoid storage fruit chromoplasts, have been recently identified leaf chloroplasts from several species and shown be induced upon environmental stress. To further investigate the role of protein, transgenic Nicotiana tabacum plants over‐expressing fibrillin using constitutive promoter were generated. Transgenics grown under standard light intensities (300 μmol photons m −2 sec −1 ) found...
The chloroplastic drought-induced stress protein of 32 kDa (CDSP32) is a thioredoxin induced by environmental conditions. To gain insight into the function CDSP32, we applied two strategies to analyze its targets. First, using affinity chromatography with an immobilized CDSP32 active site mutant, identified six plastidic targets CDSP32. Three them are involved in photosynthetic processes: ATP-ase gamma-subunit, Rubisco and aldolase. three others participate protection against oxidative...
In addition to the linear electron flow, a cyclic flow (CEF) around photosystem I occurs in chloroplasts. CEF, electrons back from donor site of plastoquinone pool via two main routes: one that involves Proton Gradient Regulation5 (PGR5)/PGRL1 complex (PGR) and is dependent NADH dehydrogenase-like complex. While importance CEF photosynthesis photoprotection has been clearly established, little known about its regulation. We worked on assumption redox regulation surveyed putative role...
Glutaredoxins (GRXs) catalyze the reduction of protein disulfide bonds using glutathione as a reductant. Certain GRXs are able to transfer iron-sulfur clusters other proteins. To investigate function Arabidopsis (Arabidopsis thaliana) GRXS17, we applied strategy combining biochemical, genetic, and physiological approaches. GRXS17 was localized in nucleus cytosol, its expression elevated shoot meristems reproductive tissues. Recombinant bound Fe2S2 clusters, property likely contributing...
Plastid lipid‐associated proteins, also termed fibrillin/CDSP34 are known to accumulate in fibrillar‐type chromoplasts such as those of ripening pepper fruit, and leaf chloroplasts from Solanaceae plants under abiotic stress conditions. It is shown here that treatments generating active oxygen species (high light combined with low temperature, gamma irradiation or methyl viologen treatment) result potato CDSP34 gene induction protein accumulation leaves. Using transgenic tomato containing...
Abstract The CDSP32 protein (chloroplastic drought-induced stress of 32 kD) is a thioredoxin participating in the defense against oxidative damage. We recently have identified vitro BAS1 2-Cys peroxiredoxin, peroxide-detoxifying enzyme, as target for CDSP32. Here, we report characterization under conditions transgenic potato (Solanum tuberosum) plants lacking with regard to redox state and level lipid peroxidation. Under control conditions, present at similar levels both wild-type (WT)...
By analysing two-dimensional patterns of chloroplastic proteins from Solanum tuberosum, the authors observed accumulation a 32-kDa polypeptide in stroma plants subjected to water deficit. N-terminus and internal peptides protein, named CDSP 32 for drought-induced stress showed no obvious homology with known sequences. Using serum raised against protein N-terminus, cDNA encoding was cloned by screening an expression library. The deduced mature is 243 amino acids long displays typical features...
We previously described the accumulation of a 34 kDa thylakoid protein, named CDSP for chloroplastic drought-induced stress in Solanum tuberosum plants subjected to water deficit. A full-length cDNA has been isolated and we report here that mature is highly similar two chromoplastic proteins, fibrillin from Capsicum annuum CHRC (for chromoplast protein C) Cucumis sativus, components carotenoid-accumulating structures. Northern Western analyses showed both transcript accumulated early stages...
Summary The 2‐cysteine peroxiredoxins (2‐Cys‐Prxs) are antioxidants that reduce peroxides through a thiol‐based mechanism. During catalysis, these ubiquitous enzymes occasionally inactivated by the substrate‐dependent oxidation of catalytic cysteine to sulfinic acid (‐SO 2 H) form, and reactivated reduction sulfiredoxin (Srx), an enzyme recently identified in yeast mammal cells. In plants, 2‐Cys‐Prxs constitute most abundant Prxs located chloroplasts. Here we have characterized unique Srx...
Methionine sulfoxide reductases (MSRs) A and B reduce methionine (MetSO) S ‐ R ‐diastereomers, respectively, back to Met using electrons generally supplied by thioredoxin. The physiological reductants for MSRBs remain unknown in plants, which display a remarkable variety of thioredoxins (Trxs) glutaredoxins (Grxs). Using recombinant proteins, we show that Arabidopsis plastidial MSRB1 MSRB2, differ regarding the number presumed redox‐active cysteines, possess specific reductants. Most...
Abstract Vitamin E is a generic term for group of lipid-soluble antioxidant compounds, the tocopherols and tocotrienols. While tocotrienols are considered as important vitamin components in humans, with functions health disease, protective have never been investigated plants, contrary to tocopherols. We took advantage strong accumulation leaves double transgenic tobacco (Nicotiana tabacum) plants that coexpressed yeast (Saccharomyces cerevisiae) prephenate dehydrogenase gene (PDH)...
Methionine oxidation to methionine sulfoxide (MetSO) is reversed by two types of reductases (MSRs), A and B, specific MetSO S- R-diastereomers, respectively. Two MSRB isoforms, MSRB1 MSRB2, are present in chloroplasts Arabidopsis thaliana. To assess their physiological role, we characterized mutants knockout for the expression MSRB1, MSRB2 or both genes. Measurements MSR activity leaf extracts revealed that plastidial enzymes account major part peptide capacity. Under standard conditions...
Thioredoxins (Trxs) are ubiquitous enzymes catalyzing the reduction of disulfide bonds, thanks to a CXXC active site. Among their substrates, 2-Cys methionine sulfoxide reductases B (2-Cys MSRBs) reduce R diastereoisomer (MetSO) and possess two redox-active Cys as follows: catalytic reducing MetSO resolving one, involved in bridge formation. The other MSRB type, 1-Cys MSRBs, possesses only Cys, regeneration mechanisms by Trxs remain unclear. plant plastidial Trx CDSP32 is able provide with...