A5008642978- Photosynthetic Processes and Mechanisms
- Metal-Catalyzed Oxygenation Mechanisms
- Metalloenzymes and iron-sulfur proteins
- Hemoglobin structure and function
- Microbial Fuel Cells and Bioremediation
- Electrochemical Analysis and Applications
- Enzyme Structure and Function
- Porphyrin Metabolism and Disorders
- Electrocatalysts for Energy Conversion
- Electrochemical sensors and biosensors
- Redox biology and oxidative stress
- Photoreceptor and optogenetics research
- Hydrogen Storage and Materials
- ATP Synthase and ATPases Research
- Trace Elements in Health
- Algal biology and biofuel production
- Electron Spin Resonance Studies
- Mitochondrial Function and Pathology
- Spectroscopy and Quantum Chemical Studies
- Microbial Community Ecology and Physiology
- Radioactive element chemistry and processing
- Nitric Oxide and Endothelin Effects
- Protein Structure and Dynamics
- Metal complexes synthesis and properties
- Heme Oxygenase-1 and Carbon Monoxide
Universidade Federal do Rio de Janeiro
2025
Universidade Nova de Lisboa
2013-2024
University of Algarve
2005-2022
Instituto Português Da Qualidade
1991-2021
Instituto de Biologia Experimental e Tecnológica
1991-2021
Stanford Medicine
2021
University College London Hospitals NHS Foundation Trust
2020
University College London
2020
Friedrich Miescher Institute
2013-2018
Instituto de Tecnología Química
2000-2014
The Bacillus subtilis endospore coat protein CotA shows laccase activity. By using comparative modeling techniques, we were able to derive a model for based on the known x-ray structures of zucchini ascorbate oxidase and Cuprinus cereneus laccase. This contains all structural features laccase, including reactive surface-exposed copper center (T1) two buried centers (T2 T3). Single amino acid substitutions in T1 (H497A, or M502L) did not prevent assembly mutant proteins into alter pattern...
Nitric oxide produced by activated macrophages plays a key role as one of the immune system's weapons against pathogens. Because lifetime nitric is short in aerobic conditions, whereas anaerobic conditions cytotoxic effects are greatly increased infection/inflammation processes, it important to establish which systems able detoxify under conditions. In present work new set Escherichia coli K-12 genes conferring resistance presented, namely gene product YtfE and potential transcriptional...
<i>Escherichia coli</i> flavorubredoxin is a member of the family A-type flavoproteins, which are built by two core domains: metallo-β-lactamase-like domain, at N-terminal region, harboring non-heme di-iron site, and flavodoxin-like containing one FMN moiety. The enzyme from<i>E. has an extra module C terminus, rubredoxin-like center. flavoproteins widespread among strict facultative anaerobes, as deduced from analysis complete prokaryotic genomes. In this report we showed that recombinant...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDetection and characterization of exchangeable protons bound to the hydrogen-activation nickel site Desulfovibrio gigas hydrogenase: a proton deuterium Q-band ENDOR studyChaoliang Fan, Miguel Teixeira, Jose Moura, Isabel Huynh Boi Hanh, Jean Le Gall, Harry D. Peck Jr., Brian M. HoffmanCite this: J. Am. Chem. Soc. 1991, 113, 1, 20–24Publication Date (Print):January 1991Publication History Published online1 May 2002Published inissue 1 January...
Summary Thiosulphate is one of the products initial step elemental sulphur oxidation pathway in thermoacidophilic archaeon Acidianus ambivalens . A novel thiosulphate:quinone oxidoreductase (TQO) activity was found membrane extracts aerobically grown cells this organism. The enzyme purified 21‐fold from solubilized fraction. TQO oxidized thiosulphate with tetrathionate as product and ferricyanide or decyl ubiquinone (DQ) electron acceptors. maximum specific 73.4 U (mg protein) −1 at 92°C pH...
The hydrogenase (EC 1.2.2.1) of Desulfovibrio gigas is a complex enzyme containing one nickel center, [3Fe-4S] and two [4Fe-4S] clusters. Redox intermediates this were generated under hydrogen (the natural substrate) using redox-titration technique studied by EPR Mossbauer spectroscopy. In the oxidized states, [4Fe-4S]2+ clusters exhibit broad quadrupole doublet with parameters (apparent delta EQ = 1.10 mm/s 0.35 mm/s) typical for type cluster. Upon reduction, [4Fe-4S]1+ are...
CO-releasing molecules (CO-RMs) were previously shown by us to be more potent bactericides than CO gas. This suggests a mechanism of action for CO-RM, which either potentiates the activity or uses another CO-RM-specific effect. We have also reported that CORM-2 induces expression genes related oxidative stress. In present study we intend establish whether generation reactive oxygen species CO-RMs may indeed result in inhibition bacterial cellular function. now report two (CORM-2 and ALF062)...
Abstract The antiscale magnetic treatment (ASMT) claims to utilize field combat scaling. However, its underlying mechanism, effectiveness, and reliability remain controversial. To address these contentious aspects, we analyze the influence of a on different stages typical scale formation, using $${\text{CaCO}}_{3}$$ as model scale. For simplification, consider working fluid, such in domestic industrial settings, homogeneous mixture supersaturated, multi-ionic solution suspension neutral...
Desulfovibrio gigas hydrogenase (EC 1.12.2.1) is a complex enzyme containing one nickel, 3Fe, and two [Fe4S4] clusters (Teixeira, M., Moura, I., Xavier, A. V., Der Vartanian, D. LeGall, J., Peck, H. D., Jr., Huynh, B. H., J. G. (1983) Eur. Biochem. 130, 481-484). This belongs to class of enzymes that are inactive as isolated (the so-called oxygen-stable hydrogenases) must go through an activation process in order express full activity. The state characterization the active centers prompted...
The hydrogenase from Desulfovibrio baculatus (DSM 1743) was purified each of three different fractions: soluble periplasmic (wash), cytoplasmic (cell disruption) and membrane‐bound (detergent solubilization). Plasma‐emission metal analysis detected in all fractions the presence iron plus nickel selenium equimolecular amounts. These hydrogenases were shown to be composed two non‐identical subunits distinct with respect their spectroscopic properties. EPR spectra native (as isolated) enzymes...
Rubredoxin-oxygen oxidoreductase (ROO) is the final component of a soluble electron transfer chain that couples NADH oxidation to oxygen consumption in anaerobic sulfate reducer<i>Desulfovibrio gigas</i>. It an 86-kDa homodimeric flavohemeprotein containing two FAD molecules, one mesoheme IX, and Fe-uroporphyrin I per monomer, capable fully reducing water. EPR studies on native enzyme reveal components with g values at ∼2.46, 2.29, 1.89, which are assigned low spin hemes similar features...
Sulfate-reducing organisms use sulfate as an electron acceptor in anaerobic respiratory process. Despite their ubiquitous occurrence, respiration is still poorly characterized. Genome analysis of sulfate-reducing sequenced to date permitted the identification only two strictly conserved membrane complexes. We report here purification and characterization one these complexes, DsrMKJOP, from Desulfovibrio desulfuricans ATCC 27774. The complex has hemes c b types several iron-sulfur centers....
DNA microarray experiments showed that the expression of Escherichia coli ytfE gene is highly increased upon exposure to nitric oxide. We also reported deletion significantly alters phenotype E. coli, generating a strain with enhanced susceptibility nitrosative stress and defective in activity several iron-sulfur-containing proteins. In this work, it shown confers protection against oxidative stress. Furthermore, we found damage [4Fe-4S]2+ clusters aconitase B fumarase A caused by hydrogen...
A sulfide:quinone oxidoreductase (SQR) was isolated from the membranes of hyperthermoacidophilic archaeon Acidianus ambivalens, and its X-ray structure, first reported for an SQR, determined to 2.6 resolution. This enzyme functionally structurally characterized shown have two redox active sites: a covalently bound FAD adjacent pair cysteine residues. Most interestingly, structure revealed presence chain three sulfur atoms bridging those The possible implications this observation in catalytic...
The abbreviations used are: (NiFe) hydrogenase, hydrogenase containing nickel and non-heme iron; (NiFeSe) equivalent amounts of selenium plus GSH, glutathione; SDS, sodium dodecyl sulfate;
Upon host infection, the protozoan parasite Entamoeba histolytica is confronted with reactive oxygen and nitrogen species must survive these stresses in order to cause invasive disease. We analysed parasite's response oxidative nitrosative stresses, probing transcriptional changes of trophozoites a pathogenic strain after 60 min exposure H2O2 (1 mM) or NO donor (dipropylenetriamine-NONOate, 200 microM), using whole-genome DNA microarrays. Genes encoding detoxification enzymes had high levels...