A5045702543- Photosynthetic Processes and Mechanisms
- Redox biology and oxidative stress
- Mitochondrial Function and Pathology
- Plant Stress Responses and Tolerance
- Photoreceptor and optogenetics research
- Metal-Catalyzed Oxygenation Mechanisms
- Advanced Proteomics Techniques and Applications
- Sulfur Compounds in Biology
- Phytase and its Applications
- Plant Molecular Biology Research
- Endoplasmic Reticulum Stress and Disease
- Legume Nitrogen Fixing Symbiosis
- ATP Synthase and ATPases Research
- Plant nutrient uptake and metabolism
- Plant Micronutrient Interactions and Effects
- Ubiquitin and proteasome pathways
- Mass Spectrometry Techniques and Applications
- Light effects on plants
- bioluminescence and chemiluminescence research
- Glutathione Transferases and Polymorphisms
- Plant Reproductive Biology
- Pharmaceutical and Antibiotic Environmental Impacts
- Plant Gene Expression Analysis
- Marine and coastal ecosystems
- Hemoglobin structure and function
Consejo Superior de Investigaciones Científicas
2010-2023
Universidad de Sevilla
2007-2023
Centro de Investigaciones Científicas Isla de la Cartuja
2003-2023
Instituto de Bioquímica Vegetal y Fotosíntesis
2007-2023
Marin Community Foundation
2010
Mercedes-Benz (Germany)
2010
Hebrew University of Jerusalem
1998-2000
Stockholm University
1991-1999
The photosystem II reaction center D1 protein is known to turn over frequently. This prone irreversible damage caused by reactive oxygen species that are formed in the light; damaged, nonfunctional degraded and replaced a new copy. However, proteases responsible for degradation remain unknown. In this study, we investigate possible role of FtsH protease, an ATP-dependent zinc metalloprotease, during process. primary light-induced cleavage product protein, 23-kD fragment, was found be...
In an attempt to identify and characterize chloroplast proteases, we performed immunological analysis of chloroplasts using antibody against Escherichia coli FtsH protease, which is ATP-dependent metalloprotease bound the cytoplasmic membrane. A cross-reacting protein 78 kDa was found in thylakoid membrane spinach, but not soluble stromal fraction. Alkali high salt washes, as well trypsin treatment membranes, suggest that chloroplastic integral membrane, with its hydrophilic portion exposed...
Abstract High irradiances may lead to photooxidative stress in plants, and non‐photochemical quenching (NPQ) contributes protection against excess excitation. One of the NPQ mechanisms, qE, involves thermal dissipation light energy captured. Importantly, plants need tune down qE under light‐limiting conditions for efficient utilization available quanta. Considering possible redox control responses implying enzymes, such as thioredoxins, we have studied role NADPH thioredoxin reductase C...
Light-dependent regulation of a growing number chloroplast enzymatic activities has been found to occur through the reversible reduction intra- or intermolecular disulphides by thioredoxins. In cyanobacteria, despite their similarity chloroplasts, no proteins have hitherto shown interact with thioredoxins, and role cyanobacterial ferredoxin/thioredoxin system remained obscure. By using an immobilized cysteine 35-to-serine site-directed mutant Synechocystis sp. PCC 6803 thioredoxin TrxA as...
An endogenous proteolytic activity associated with spinach chloroplast thylakoid membranes has been identified. This enzymic is involved in the degradation of major light-harvesting chlorophyll a/b protein photosystem II (LHCII) response to exposure leaves increased irradiance. proteolysis LHCII requires an induction period and can only be detected 48-72 hours after transfer plants from low-intensity high-intensity light. Once initiated by light, readily occur complete darkness. The can,...
The proteases involved in proteolytic degradation the thylakoid lumen are largely unknown. Western analysis with an antibody against Escherichia coli periplasmic serine protease DegP suggested that pea chloroplasts contain a homologue of this protease. This was peripherally bound to luminal side membrane and could only be removed by combination high salt non-ionic detergent. Its level increased almost 2-fold seedlings exposed elevated temperature for 4 h, suggesting protease's role...
Abstract The light‐dependent regulation of stromal enzymes by thioredoxin (Trx)‐catalysed disulphide/dithiol exchange is known as a classical mechanism for control chloroplast metabolism. Recent proteome studies show that Trx targets are present not only in the stroma but all compartments, from envelope to thylakoid lumen. Trx‐mediated redox appears be common feature important pathways, such Calvin cycle, starch synthesis and tetrapyrrole biosynthesis. However, extent thiol‐dependent lumen...
Redox regulation plays a central role in the adaptation of chloroplast metabolism to light. Extensive biochemical analyses vitro have identified f-type thioredoxins (Trxs) as most important catalysts for light-dependent reduction and activation enzymes Calvin–Benson cycle. However, precise function type f Trxs vivo their impact on plant growth are still poorly known. To address this issue we generated an Arabidopsis thaliana double knock-out mutant, termed trxf1f2, devoid both f1 f2 Trxs....
Most plants have the ability to respond fluctuations in light minimize damage photosynthetic apparatus. A proteolytic activity has been discovered that is involved degradation of major light-harvesting chlorophyll a/b-binding protein photosystem II (LHCII) when antenna size reduced upon acclimation from low high intensities. This ATP-dependent serine or cysteine type and associated with outer membrane surface stroma-exposed thylakoid regions. The identity protease not known, but it does...
The early light‐inducible proteins (ELIPs) in chloroplasts possess a high sequence homology with the chlorophyll a/b ‐binding but differ from those by their substoichiometric and transient appearance. In present study ELIPs of pea were isolated two‐step purification strategy: perfusion chromatography combination preparative isoelectric focussing. Two heterogeneous populations obtained after chromatographic separation solubilized thylakoid membranes using weak anion exchange column. One these...
Iron limitation is the major factor controlling phytoplankton growth in vast regions of contemporary oceans. In this study, a combination thermoluminescence, chlorophyll fluorescence and P700 absorbance measurements have been used to elucidate effects iron deficiency photosynthetic electron transport marine diatom Phaeodactylum tricornutum. Thermoluminescence was determine on Photosystem II activity. Excitation iron-replete tricornutum cells with single turn-over flashes induced appearance...
Coagulation-flocculation is a critical treatment to reduce operational problems at Drinking Water Treatment Plants (DWTPs), created by episodes of cyanobacterial blooms in surface waters. There need for the search good coaguflocculants that avoid release intracellular toxins safer sustainable production. Clay-polymer interactions were examined development efficient composites their use as Microcystis aeruginosa (M. aeruginosa) suspensions. Polymers derived from poly-4-vinylpyridine (PVP)...
Cyanobacteria perform oxygenic photosynthesis, which gives rise to the continuous production of reactive oxygen species, such as superoxide anion radicals and hydrogen peroxide, particularly under unfavorable growth conditions. Peroxiredoxins, are present in both chloroplasts cyanobacteria, constitute a class thiol-dependent peroxidases capable reducing peroxide well alkyl hydroperoxides. Chloroplast peroxiredoxins have been studied extensively found use variety endogenous electron donors,...
Cysteine dithiol/disulphide exchange forms the molecular basis for regulation of a wide variety enzymatic activities and transduction cellular signals. Thus, search proteins with reactive, accessible cysteines is expected to contribute unravelling new mechanisms enzyme signal transduction. Several methods have been designed this purpose taking advantage interactions between thioredoxins their protein substrates. Thioredoxins comprise family redox-active enzymes, which catalyse reduction...
Abstract The precise timing of flowering in adverse environments is critical for plants to secure reproductive success. We report a mechanism Arabidopsis (Arabidopsis thaliana) controlling the time by which S-acylation-dependent nuclear import protein SALT OVERLY SENSITIVE3/CALCINEURIN B-LIKE4 (SOS3/CBL4), Ca2+-signaling intermediary plant response salinity, results selective stabilization regulator GIGANTEA inside nucleus under salt stress, while degradation cytosol releases kinase SOS2...
Searching for enzymes and other proteins which can be redox-regulated by dithiol/disulphide exchange is a rapidly expanding area of functional proteomics. Recently, several experimental approaches using thioredoxins have been developed this purpose. Thioredoxins comprise large family redox-active capable reducing protein disulphides to cysteines participating in variety processes, such as enzyme modulation, donation equivalents signal transduction. In study we screened the target proteomes...
Abstract Redox regulation based on disulfide-dithiol conversion catalyzed by thioredoxins is an important component of chloroplast function. The reducing power provided ferredoxin reduced the photosynthetic electron transport chain. In addition, chloroplasts are equipped with a peculiar NADPH-dependent thioredoxin reductase, termed NTRC, joint domain at carboxyl terminus. Because NADPH can be produced oxidative pentose phosphate pathway during night, NTRC to maintain redox homeostasis under...
Photosynthesis, the primary source of biomass and oxygen into biosphere, involves transport electrons in presence and, therefore, chloroplasts constitute an important reactive species, including hydrogen peroxide. If accumulated at high level, peroxide may exert a toxic effect; however, it is as well second messenger. In order to balance signaling activities its level has be tightly controlled. To this end, are equipped with different antioxidant systems such 2-Cys peroxiredoxins (2-Cys...
Protein phosphorylation is a principal signaling mechanism that mediates regulation of enzymatic activities, modulation gene expression, and adaptation to environmental changes. Recent studies have shown ubiquitous distribution eukaryotic-type Serine/Threonine protein kinases in prokaryotic genomes, though the functions, substrates, possible these enzymes remain largely unknown. In this study, we investigated whether cyanobacterial may be subject redox through cysteine state, as has...