A5060725367- Hemoglobin structure and function
- Photosynthetic Processes and Mechanisms
- Metalloenzymes and iron-sulfur proteins
- Heme Oxygenase-1 and Carbon Monoxide
- Porphyrin Metabolism and Disorders
- Metal-Catalyzed Oxygenation Mechanisms
- Microbial Fuel Cells and Bioremediation
- Trace Elements in Health
- Neonatal Health and Biochemistry
- Education Pedagogy and Practices
- Bacterial Genetics and Biotechnology
- Microbial Community Ecology and Physiology
- Enzyme Structure and Function
- Bacterial biofilms and quorum sensing
- Redox biology and oxidative stress
- Nitric Oxide and Endothelin Effects
- Electron Spin Resonance Studies
- Antimicrobial Resistance in Staphylococcus
- Photoreceptor and optogenetics research
- Iron Metabolism and Disorders
- Helicobacter pylori-related gastroenterology studies
- Algal biology and biofuel production
- Porphyrin and Phthalocyanine Chemistry
- Education and Digital Technologies
- Business and Management Studies
Universidade Nova de Lisboa
2016-2025
Universidade Federal de Minas Gerais
2016-2021
Universidade Federal de Viçosa
2010-2019
Instituto de Biologia Experimental e Tecnológica
1990-2018
Universidade do Porto
2015-2018
Escola Universitária Vasco da Gama
2013-2016
Universidade Federal de Sergipe
2016
University of Trás-os-Montes and Alto Douro
2015-2016
Instituto de Tecnología Química
2004-2015
Open Ephys Production Site (Portugal)
2014-2015
Apoptosis-inducing factor (AIF) is a mitochondrial flavoprotein, which translocates to the nucleus during apoptosis and causes chromatin condensation large scale DNA fragmentation. Here we report biochemical characterization of AIF's redox activity. Natural AIF purified from mitochondria recombinant bacteria (AIFΔ1–120) exhibit NADH oxidase activity, whereas superoxide anion (O2−) formed. AIFΔ1–120 monomer 57 kDa containing 1 mol noncovalently bound FAD/mol protein. ApoAIFΔ1–120, lacks FAD,...
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...
ABSTRACT Carbon monoxide (CO) is endogenously produced in the human body, mainly from oxidation of heme catalyzed by oxygenase (HO) enzymes. The induction HO and consequent increase CO production play important physiological roles vasorelaxation neurotransmission immune system. exogenous administration gas CO-releasing molecules (CO-RMs) has been shown to induce vascular effects alleviate hypoxia-reoxygenation injury mammalian cells. In particular, due its anti-inflammatory, antiapoptotic,...
Brain accumulation of soluble amyloid-β oligomers (AβOs) has been implicated in synapse failure and cognitive impairment Alzheimer's disease (AD). However, whether how different sizes induce dysfunction is a matter controversy. Here, we report that low-molecular-weight (LMW) high-molecular-weight (HMW) Aβ differentially impact synapses memory. A single intracerebroventricular injection LMW AβOs (10 pmol) induced rapid persistent mice. On the other hand, memory deficit by HMW was found to be...
Abstract We demonstrate that Ru II (CO) 2 –protein complexes, formed by the reaction of hydrolytic decomposition products [ fac ‐RuCl( κ ‐H NCH CO )(CO) 3 ] (CORM‐3) with histidine residues exposed on surface proteins, spontaneously release in aqueous solution, cells, and mice. was detected mass spectrometry (MS) confocal microscopy using a CO‐responsive turn‐on fluorescent probe. These findings support our hypothesis plasma proteins act as carriers after vivo administration CORM‐3. released...
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)...
Modified tetrapyrroles such as chlorophyll, heme, siroheme, vitamin B 12 , coenzyme F 430 and heme d 1 underpin a wide range of essential biological functions in all domains life, it is therefore surprising that the syntheses many these life pigments remain poorly understood. It known construction central molecular framework modified mediated via common, core pathway. Herein further branch tetrapyrrole biosynthesis pathway described denitrifying sulfate-reducing bacteria well Archaea. This...
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...
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...
Tuberculosis associates with a wide spectrum of disease outcomes. The Beijing (Bj) lineage Mycobacterium tuberculosis (Mtb) is suggested to be more virulent than other Mtb lineages and prone elicit non-protective immune responses. However, highly heterogeneous responses were reported upon infection innate cells Bj strains or stimulation their glycolipids. Using both in vitro vivo mouse models infection, we here report that the molecular mechanism for this heterogeneity may related distinct...
Summary Haem is a life supporting molecule that ubiquitous in all major kingdoms. In S taphylococcus aureus , the importance of haem highlighted by presence systems both for exogenous acquisition and endogenous synthesis this prosthetic group. work, we show . formation involves conversion coproporphyrinogen III into coproporphyrin synthase HemY insertion iron via ferrochelatase HemH oxidative decarboxylation Fe ‐coproporphyrin protohaem IX oxidase/dehydrogenase HemQ Together, route...
Transition metal carbonyl complexes used as CO-releasing molecules (CORMs) for biological and therapeutic applications may exhibit interesting antimicrobial activity. However, understanding the chemical traits mechanisms of action that rule this activity is required to establish a rationale development CORMs into useful antibiotics. In work bactericidal activity, toxicity eukaryotic cells, ability deliver CO bacterial cells were analysed set seven differ in transition metal, ancillary...
Several metal-based carbon monoxide-releasing molecules (CORMs) are active CO donors with established antibacterial activity. Among them, CORM conjugates azole antibiotics of type [Mn(CO)3(2,2'-bipyridyl)(azole)]+ display important synergies against several microbes. We carried out a structure-activity relationship study based upon the lead structure [Mn(CO)3(Bpy)(Ctz)]+ by producing clotrimazole (Ctz) varying metal and ligands. concluded that nature bidentate ligand strongly influences...
Expression of two genes unknown function, Staphylococcus aureus scdA and Neisseria gonorrhoeae dnrN, is induced by exposure to oxidative or nitrosative stress. We show that DnrN ScdA are di-iron proteins protect their hosts from damage caused nitric oxide hydrogen peroxide. Loss FNR-dependent activation aniA expression NsrR-dependent repression norB dnrN on NO was restored in the gonococcal parent strain but not a mutant, suggesting necessary for repair transcription factors, FNR NsrR....
Hybrid cluster proteins (HCP) contain two types of Fe/S clusters, namely a [4Fe-4S](2+/1+) or [2Fe-2S](2+/1+) and novel type hybrid cluster, [4Fe-2S-2O], in the as-isolated state. Although first isolated from anaerobic sulfate-reducing bacteria, analysis genomic sequences reveals that genes encoding putative are present wide range organisms, aerobic, anaerobic, facultative, Bacteria, Archaea, Eukarya domains. Despite detailed spectroscopic structural characterization, precise physiological...
We recently reported that carbon monoxide (CO) has bactericidal activity. To understand its mode of action we analysed the gene expression changes occurring when Escherichia coli, grown aerobically and anaerobically, is treated with CO-releasing molecule CORM-2 (tricarbonyldichlororuthenium(II) dimer). Microarray analysis shows E. coli response multifaceted, a high number differentially regulated genes spread through several functional categories, namely involved in inorganic ion transport...
Our previous analysis of the transcriptome Escherichia coli under nitrosative stress showed that ytfE gene was one highest induced genes. Furthermore, E. strain mutated on found to be more sensitive nitric oxide than wild-type strain. In present work, we show mutation in yielded a grows poorly anaerobic respiratory conditions and has an increased sensitivity iron starvation. all examined iron–sulphur proteins have decreased activity levels lacking ytfE. Altogether, results suggest role for...
Sulfate reducing bacteria of the Desulfovibrio genus are considered anaerobes, in spite fact that they frequently isolated close to oxic habitats. However, until now, growth presence high concentrations oxygen was not reported for members this genus. This work shows first time sulfate bacterium desulfuricans ATCC 27774 is able grow nearly atmospheric levels. In addition, activity and expression profile several key enzymes analyzed under different concentrations.
Trichomonas vaginalis is one of a few eukaryotes that have been found to encode several homologues flavodiiron proteins (FDPs). Widespread among anaerobic prokaryotes, these are believed function as oxygen and/or nitric oxide reductases provide protection against oxidative/nitrosative stresses and host immune responses. One the T. FDP equipped with hydrogenosomal targeting sequence expressed in hydrogenosomes, oxygen-sensitive organelles participate carbohydrate metabolism assemble...
Helicobacter pylori is a pathogen that establishes long life infections responsible for chronic gastric ulcer diseases and proved risk factor carcinoma. The therapeutic properties of carbon-monoxide releasing molecules (CORMs) led us to investigate their effect on H. pylori. We show 26695 susceptible two widely used CORMs, namely CORM-2 CORM-3. Also, several clinical isolates were killed by CORM-2, including those resistant metronidazole. Moreover, sub-lethal doses combined with...