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2004
dos Santos, MMC, Sousa PMP, Goncalves MLS, Romao MJ, Moura I, Moura JJG.  2004.  Direct electrochemistry of the Desulfovibrio gigas aldehyde oxidoreductase. European Journal of Biochemistry. 271:1329-1338., Number 7 AbstractWebsite
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Valente, AA, Petrovski Z, Branco LC, Afonso CAM, Pillinger M, Lopes AD, Romao CC, Nunes CD, Goncalves IS.  2004.  Epoxidation of cyclooctene catalyzed by dioxomolybdenum(VI) complexes in ionic liquids. Journal of Molecular Catalysis a-Chemical. 218:5-11., Number 1 AbstractWebsite
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Carvalho, AL, Goyal A, Prates JAM, Bolam DN, Gilbert HJ, Pires VMR, Ferreira LMA, Planas A, Romao MJ, Fontes C.  2004.  The family 11 carbohydrate-binding module of Clostridium thermocellum Lic26A-Cel5E accommodates beta-1,4- and beta-1,3-1,4-mixed linked glucans at a single binding site. Journal of Biological Chemistry. 279:34785-34793., Number 33 AbstractWebsite
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Faustino, P, Miranda A, Silva MD, Alves C, Pinanco I, Ferreira C, Seixas MT, Pina F, Romao L.  2004.  Hb Yaounde beta 134(H12)Val -> Ala in association with Hb C beta 6(A3)Glu -> Lys in a Caucasian Portuguese family. Hemoglobin. 28:229-235., Number 3 AbstractWebsite
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Gago, S, Pillinger M, Valente AA, Santos TM, Rocha J, Goncalves IS.  2004.  Immobilization of oxomolybdenum species in a layered double hydroxide pillared by 2,2 '-bipyridine-5,5 '-dicarboxylate anions. Inorganic Chemistry. 43:5422-5431., Number 17 AbstractWebsite
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Abrantes, M, Gago S, Valente AA, Pillinger M, Goncalves IS, Santos TM, Rocha J, Romao CC.  2004.  Incorporation of a (cyclopentadienyl)molybdenum oxo complex in MCM-41 and its use as a catalyst for olefin epoxidation. European Journal of Inorganic Chemistry. :4914-4920., Number 24 AbstractWebsite
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Moura, JJG, Brondino CD, Trincao J, Romao MJ.  2004.  Mo and W bis-MGD enzymes: nitrate reductases and formate dehydrogenases. Journal of Biological Inorganic Chemistry. 9:791-799., Number 7 AbstractWebsite
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Hettmann, T, Siddiqui RA, Frey C, Santos-Silva T, Romao MJ, Diekmann S.  2004.  Mutagenesis study on amino acids around the molybdenum centre of the periplasmic nitrate reductase from Ralstonia eutropha. Biochemical and Biophysical Research Communications. 320:1211-1219., Number 4 AbstractWebsite
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Dias, JM, Alves T, Bonifacio C, Pereira AS, Trincao J, Bourgeois D, Moura I, Romao MJ.  2004.  Structural basis for the mechanism of Ca2+ activation of the di-heme cytochrome c peroxidase from Pseudomonas nautica 617. Structure. 12:961-973., Number 6 AbstractWebsite
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Gago, S, Zhang YM, Santos AM, Kohler K, Kuhn FE, Fernandes JA, Pillinger M, Valente AA, Santos TM, Ribeiro-Claro PJA, Goncalves IS.  2004.  Synthesis and characterization of a manganese(II) acetonitrile complex supported on functionalized MCM-41. Microporous and Mesoporous Materials. 76:131-136., Number 1-3 AbstractWebsite
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Gago, S, Pillinger M, Santos TM, Rocha J, Goncalves IS.  2004.  Synthesis and properties of Zn-Al layered double hydroxides containing ferrocenecarboxylate anions. European Journal of Inorganic Chemistry. :1389-1395., Number 7 AbstractWebsite
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Ferrer, M, Rodriguez L, Rossell O, Lima JC, Gomez-Sal P, Martin A.  2004.  Unexpected alkyne transfer between gold and rhenium atoms and its application to the synthesis of alkynyl rhenium(I) compounds. Organometallics. 23:5096-5099., Number 21 Abstract
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Boer, DR, Thapper A, Brondino CD, Romao MJ, Moura JJG.  2004.  X-ray crystal structure and EPR spectra of "arsenite-inhibited" Desulfovibrio gigas aldehyde dehydrogenase: A member of the xanthine oxidase family. Journal of the American Chemical Society. 126:8614-8615., Number 28 AbstractWebsite
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Helberger, N, Kerényi K, Krings B, Lambers R, Orwat C, Riehm U, van Gompel S, Dufft N.  2004.  {Digital Rights Management and Consumer Acceptability: A Multi-Disciplinary Discussion of Consumer Concerns and Expectations}. , Number 6641: University Library of Munich, Germany Abstract

The INDICARE project – the Informed Dialogue about Consumer Acceptability of DRM Solutions in Europe – has been set up to raise awareness about consumer and user issues of Digital Rights Management (DRM) solutions. One of the main goals of the INDICARE project is to contribute to the consensus-building among multiple players with heterogeneous interests in the digital environment. To promote this process and to contribute to the creation of a common level of understanding is the aim of the present report. It provides an overview of consumer concerns and expectations regarding DRMs, and discusses the findings from a social, legal, technical and business perspective. A general overview of the existing EC initiatives shows that questions of consumer acceptability of DRM have only recently begun to draw wider attention. A review of the relevant statements, studies and reports confirms that awareness of consumer concerns is still at a low level. Five major categories of concerns have been distinguished so far: (1) fair conditions of use and access to digital content, (2) privacy, (3) interoperability, (4) transparency and (5) various aspects of consumer friendliness. From the legal point of view, many of the identified issues go beyond the scope of copyright law, i.e. the field of law where DRM was traditionally discussed. Often they are a matter of general or sector-specific consumer protection law. Furthermore, it is still unclear to what extent technology and an appropriate design of technical solutions can provide an answer to some of the concerns of consumers. One goal of the technical chapter was exactly to highlight some of these technical possibilities. Finally, it is shown that consumer acceptability of DRM is important for the economic success of different business models based on DRM. Fair and responsive DRM design can be a profitable strategy, however DRM-free alternatives do exist too.

2003
Banci, L, Bertini I, Felli IC, Krippahl L, Kubicek K, Moura JJ, Rosato A.  2003.  A further investigation of the cytochrome b5-cytochrome c complex, Sep. J Biol Inorg Chem. 8:777-86., Number 7 AbstractWebsite

The interaction of reduced rabbit cytochrome b(5) with reduced yeast iso-1 cytochrome c has been studied through the analysis of (1)H-(15)N HSQC spectra, of (15)N longitudinal ( R(1)) and transverse ( R(2)) relaxation rates, and of the solvent exchange rates of protein backbone amides. For the first time, the adduct has been investigated also from the cytochrome c side. The analysis of the NMR data was integrated with docking calculations. The result is that cytochrome b(5) has two negative patches capable of interacting with a single positive surface area of cytochrome c. At low protein concentrations and in equimolar mixture, two different 1:1 adducts are formed. At high concentration and/or with excess cytochrome c, a 2:1 adduct is formed. All the species are in fast exchange on the scale of differences in chemical shift. By comparison with literature data, it appears that the structure of one 1:1 adduct changes with the origin or primary sequence of cytochrome b(5).

Almeida, MG, Macieira S, Goncalves LL, Huber R, Cunha CA, Romao MJ, Costa C, Lampreia J, Moura JJ, Moura I.  2003.  The isolation and characterization of cytochrome c nitrite reductase subunits (NrfA and NrfH) from Desulfovibrio desulfuricans ATCC 27774. Re-evaluation of the spectroscopic data and redox properties, Oct. Eur J Biochem. 270:3904-15., Number 19 AbstractWebsite

The cytochrome c nitrite reductase is isolated from the membranes of the sulfate-reducing bacterium Desulfovibrio desulfuricans ATCC 27774 as a heterooligomeric complex composed by two subunits (61 kDa and 19 kDa) containing c-type hemes, encoded by the genes nrfA and nrfH, respectively. The extracted complex has in average a 2NrfA:1NrfH composition. The separation of ccNiR subunits from one another is accomplished by gel filtration chromatography in the presence of SDS. The amino-acid sequence and biochemical subunits characterization show that NrfA contains five hemes and NrfH four hemes. These considerations enabled the revision of a vast amount of existing spectroscopic data on the NrfHA complex that was not originally well interpreted due to the lack of knowledge on the heme content and the oligomeric enzyme status. Based on EPR and Mossbauer parameters and their correlation to structural information recently obtained from X-ray crystallography on the NrfA structure [Cunha, C.A., Macieira, S., Dias, J.M., Almeida, M.G., Goncalves, L.M.L., Costa, C., Lampreia, J., Huber, R., Moura, J.J.G., Moura, I. & Romao, M. (2003) J. Biol. Chem. 278, 17455-17465], we propose the full assignment of midpoint reduction potentials values to the individual hemes. NrfA contains the high-spin catalytic site (-80 mV) as well as a quite unusual high reduction potential (+150 mV)/low-spin bis-His coordinated heme, considered to be the site where electrons enter. In addition, the reassessment of the spectroscopic data allowed the first partial spectroscopic characterization of the NrfH subunit. The four NrfH hemes are all in a low-spin state (S = 1/2). One of them has a gmax at 3.55, characteristic of bis-histidinyl iron ligands in a noncoplanar arrangement, and has a positive reduction potential.

Cunha, CA, Macieira S, Dias JM, Almeida G, Goncalves LL, Costa C, Lampreia J, Huber R, Moura JJ, Moura I, Romao MJ.  2003.  Cytochrome c nitrite reductase from Desulfovibrio desulfuricans ATCC 27774. The relevance of the two calcium sites in the structure of the catalytic subunit (NrfA), May 9. J Biol Chem. 278:17455-65., Number 19 AbstractWebsite

The gene encoding cytochrome c nitrite reductase (NrfA) from Desulfovibrio desulfuricans ATCC 27774 was sequenced and the crystal structure of the enzyme was determined to 2.3-A resolution. In comparison with homologous structures, it presents structural differences mainly located at the regions surrounding the putative substrate inlet and product outlet, and includes a well defined second calcium site with octahedral geometry, coordinated to propionates of hemes 3 and 4, and caged by a loop non-existent in the previous structures. The highly negative electrostatic potential in the environment around hemes 3 and 4 suggests that the main role of this calcium ion may not be electrostatic but structural, namely in the stabilization of the conformation of the additional loop that cages it and influences the solvent accessibility of heme 4. The NrfA active site is similar to that of peroxidases with a nearby calcium site at the heme distal side nearly in the same location as occurs in the class II and class III peroxidases. This fact suggests that the calcium ion at the distal side of the active site in the NrfA enzymes may have a similar physiological role to that reported for the peroxidases.

Rodrigues, CM, Sola S, Sharpe JC, Moura JJ, Steer CJ.  2003.  Tauroursodeoxycholic acid prevents Bax-induced membrane perturbation and cytochrome C release in isolated mitochondria, Mar 18. Biochemistry. 42:3070-80., Number 10 AbstractWebsite

Bax is a potent pro-apoptotic member of the Bcl-2 protein family that localizes to the mitochondrial membrane during apoptosis. Tauroursodeoxycholic acid (TUDCA) modulates the apoptotic threshold, in part, by preventing Bax translocation both in vitro and in vivo. The mechanisms by which Bax induces and TUDCA inhibits release of cytochrome c are unclear. We show here that recombinant Bax protein induced cytochrome c release in isolated mitochondria without detectable swelling. Co-incubation with TUDCA prevented efflux of mitochondrial factors and proteolytic processing of caspases in cytosolic extracts. Spectroscopic analyses of mitochondria exposed to Bax revealed increased polarity and fluidity of the membrane lipid core as well as altered protein order, indicative of Bax binding, together with loss of spin-label paramagnetism, characteristic of oxidative damage. TUDCA markedly abrogated the Bax-induced membrane perturbation. In conclusion, our results indicate that Bax protein directly induces cytochrome c release from mitochondria through a mechanism that does not require the permeability transition. Rather, it is accompanied by changes in the organization of membrane lipids and proteins. TUDCA is a potent inhibitor of Bax association with mitochondria. Thus, TUDCA modulates apoptosis by suppressing mitochondrial membrane perturbation through pathways that are also independent of the mitochondrial permeability transition.

Moura, I, Cabrito I, Almeida G, Cunha C, Romao MJ, Moura JJG.  2003.  Molecular aspects of denitrification/nitrate dissimilation, Jul 15. Journal of Inorganic Biochemistry. 96:195-195., Number 1 AbstractWebsite
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Goodfellow, BJ, Rusnak F, Moura I, Ascenso CS, Moura JJ.  2003.  NMR solution structures of two mutants of desulforedoxin, Jan 1. J Inorg Biochem. 93:100-8., Number 1-2 AbstractWebsite

The differences in geometry at the metal centres in the two known [Fe-4S] proteins rubredoxin (Rd) and desulforedoxin (Dx) are postulated to be a result of the different spacing of the C-terminal cysteine pair in the two proteins. In order to address this question, two mutants of Desulfovibrio gigas Dx with modified cysteinyl spacing were prepared and their solution structures have been determined by NMR. Mutant 1 of Dx (DxM1) has a single glycine inserted between the adjacent cysteines (C28 and C29) found in the wild type Dx sequence. Mutant 3 (DxM3) has two amino acid residues, -P-V-, inserted between C28 and C29 in order to mimic the primary sequence found in Rd from Desulfovibrio gigas. The solution structure of DxM1 exists, like wild type Dx, as a dimer in solution although the single glycine inserted between the adjacent cysteines disrupts the stability of the dimer resulting in exchange between a dimer state and a small population of another, probably monomeric, state. For DxM3 the two amino acid residues inserted between the adjacent cysteines results in a monomeric protein that has a global fold near the metal centre very similar to that found in Rd.

Auchere, F, Raleiras P, Benson L, Venyaminov SY, Tavares P, Moura JJ, Moura I, Rusnak F.  2003.  Formation of a stable cyano-bridged dinuclear iron cluster following oxidation of the superoxide reductases from Treponema pallidum and Desulfovibrio vulgaris with K(3)Fe(CN)(6), Feb 24. Inorg Chem. 42:938-40., Number 4 AbstractWebsite

Superoxide reductases catalyze the monovalent reduction of superoxide anion to hydrogen peroxide. Spectroscopic evidence for the formation of a dinuclear cyano-bridged adduct after K(3)Fe(CN)(6) oxidation of the superoxide reductases neelaredoxin from Treponema pallidum and desulfoferrodoxin from Desulfovibrio vulgaris was reported. Oxidation with K(3)Fe(CN)(6) reveals a band in the near-IR with lambda(max) at 1020 nm, coupled with an increase of the iron content by almost 2-fold. Fourier transform infrared spectroscopy provided additional evidence with CN-stretching vibrations at 2095, 2025-2030, and 2047 cm(-)(1), assigned to a ferrocyanide adduct of the enzyme. Interestingly, the low-temperature electronic paramagnetic resonance (EPR) spectra of oxidized TpNlr reveal at least three different species indicating structural heterogeneity in the coordination environment of the active site Fe ion. Given the likely 6-coordinate geometry of the active site Fe(3+) ion in the ferrocyanide adduct, we propose that the rhombic EPR species can serve as a model of a hexacoordinate form of the active site.

Rodrigues, PM, Moura I, Macedo AL, Moura JJG.  2003.  Spectroscopic characterization of a novel 2 x 4Fe-4S ferredoxin isolated from Desulfovibrio desulfuricans ATCC 27774, Dec 3. Inorganica Chimica Acta. 356:215-221. AbstractWebsite

A novel iron-sulfur containing protein, a ferredoxin (Fd), was purified to homogeneity from the extract of Desulfovibrio desulfuricans American type culture collection (ATCC) 27774. The purified protein is a 13.4 kDa homodimer with a polypeptide chain of 60 amino acids residues, containing eight cysteines that coordinate two [4Fe-4S] clusters. The protein is shown to be air sensitive and cluster conversions take place. We structurally characterize a redox state that contains two [4Fe-4S] cores. 1D and 2D H-1 NMR studies are reported on form containing the clusters in the oxidized state. Based on the nuclear Overhauser effect (NOE), relaxation measurements and comparison of the present data with the available spectra of the analogous 8Fe Fds, the cluster ligands were specifically assigned to the eight-cysteinyl residues. (C) 2003 Elsevier B.V. All rights reserved.

Timóteo, {AT}, Abecassis M, Baptista P, Rebocho {MJ, {Queiroz E Melo} J.  2003.  Óxido Nítrico na Abordagem da Hipertensão Pulmonar no Contexto de Cirurgia Cardíaca do Adulto, dec. Revista Portuguesa de Cardiologia. 22:1503–1511., Number 12: Sociedade Portuguesa de Cardiologia | Elsevier Abstract

Pulmonary hypertension is a significant problem to take into account in the post-operative management of cardiac patients, especially valvular patients. Inhaled nitric oxide allows more effective control of pulmonary pressure and other hemodynamic parameters, with better post-operative results. We present a clinical case of a patient with mitral stenosis and severe pulmonary hypertension, with post-operative hemodynamic instability, in which we used inhaled nitric oxide for better control of pulmonary pressures and to help ventilator weaning.

Rodriguez, L, Alves S, Lima JC, Parola AJ, Pina F, Soriano C, Albelda T, Garcia-Espana E.  2003.  Supramolecular interactions of hexacyanocobaltate(III) with polyamine receptors containing a terminal anthracene sensor, 2003. Journal of Photochemistry and Photobiology a-Chemistry. 159:253-258. AbstractWebsite

The fluorescence emission properties of a series of chemosensors containing a polyamine receptor bearing an anthracene signaling unit were studied. The fluorescence emission intensity is dependent on the protonation degree of the receptor, the fully protonated form exhibiting the highest emission intensity. By removing protons from the nitrogens a quenching effect can be observed, due to an electron-transfer from the amine to the excited fluorophore. The rate constant of the quenching process is exponentially dependent on the distance of the nitrogen from which the electron is transferred (beta = 0.6Angstrom(-1)). The ability of the chemosensors for signaling anions was tested through the model anion hexacyanocobaltate(III). The temperature dependence of the association constants shows that at least for this compound, the change in solvation entropy is probably the controlling parameter to account for the binding. (C) 2003 Elsevier Science B.V. All rights reserved.

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