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1992
Parola, AJ, Pina F.  1992.  PHOTOCHEMISTRY OF THE ADDUCT BETWEEN CO(CN)5H2O 2- AND THE POLYAMMONIUM MACROCYCLIC RECEPTOR 32 ANE-N8 - EVIDENCE FOR THE SUPRAMOLECULAR STRUCTURE, 1992. Journal of Photochemistry and Photobiology a-Chemistry. 66:337-343. AbstractWebsite

The photochemistry of aqueous solutions of [Co(CN)5H2O]2- in the presence of the polyammonium macrocyclic receptor [32]ane-N8H88+ was studied. The quantum yield for cyanide release in free [Co(CN)5H2O]2- (PHI = 0.003 at 313 nm, pH 1.5) is reduced approximately threefold in the presence of the protonated macrocycle, which provides evidence for the formation of a supramolecular structure. Further evidence for the supramolecular structure is obtained from the thermal anation of [Co(CN)5H2O]2- with Br- (40-degrees-C, pH 1.0), the rate of which is increased in the presence of [32]ane-N8H88+, suggesting that the ligand water is not involved in hydrogen bonds with the macrocycle. These results are interpreted in terms of possible supramolecular structures.

Burrows, HD, Cardoso AC, Formosinho SJ, Gil AMPC, da Miguel MGM, Barata B, J.G. Moura J.  1992.  The photochemical reaction between uranyl nitrate and azulene. Journal of Photochemistry and Photobiology A: Chemistry. 68:279-287., Number 3 AbstractWebsite
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Melo, MJ, Pina F, Macanita AL, Melo EC, Herrmann C, Forster R, Koch H, Wamhoff H.  1992.  PHOTOCHEMISTRY OF 2-(2-FURYL)-BENZIMIDAZOLE (FUBERIDAZOLE). Zeitschrift Fur Naturforschung Section B-a Journal of Chemical Sciences. 47:1431-1437., Number 10 AbstractWebsite
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1990
Moura, I, Tavares P, Moura JJ, Ravi N, Huynh BH, Liu MY, Legall J.  1990.  Purification and characterization of desulfoferrodoxin. A novel protein from Desulfovibrio desulfuricans (ATCC 27774) and from Desulfovibrio vulgaris (strain Hildenborough) that contains a distorted rubredoxin center and a mononuclear ferrous center, Dec 15. J Biol Chem. 265:21596-602., Number 35 AbstractWebsite

A new type of non-heme iron protein was purified to homogeneity from extracts of Desulfovibrio desulfuricans (ATCC 27774) and Desulfovibrio vulgaris (strain Hildenborough). This protein is a monomer of 16-kDa containing two iron atoms per molecule. The visible spectrum has maxima at 495, 368, and 279 nm and the EPR spectrum of the native form shows resonances at g = 7.7, 5.7, 4.1 and 1.8 characteristic of a high-spin ferric ion (S = 5/2) with E/D = 0.08. Mossbauer data indicates the presence of two types of iron: an FeS4 site very similar to that found in desulforedoxin from Desulfovibrio gigas and an octahedral coordinated high-spin ferrous site most probably with nitrogen/oxygen-containing ligands. Due to this rather unusual combination of active centers, this novel protein is named desulfoferrodoxin. Based on NH2-terminal amino acid sequence determined so far, the desulfoferrodoxin isolated from D. desulfuricans (ATCC 27774) appears to be a close analogue to a recently discovered gene product from D. vulgaris (Brumlik, M.J., and Voordouw, G. (1989) J. Bacteriol. 171, 49996-50004), which was suggested to be a rubredoxin oxidoreductase. However, reduced pyridine nucleotides failed to reduce the desulforedoxin-like center of this new protein.

Fauque, G, Lino AR, Czechowski M, Kang L, Dervartanian DV, Moura JJ, Legall J, Moura I.  1990.  Purification and characterization of bisulfite reductase (desulfofuscidin) from Desulfovibrio thermophilus and its complexes with exogenous ligands, Aug 1. Biochim Biophys Acta. 1040:112-8., Number 1 AbstractWebsite

A dissimilatory bisulfite reductase has been purified from a thermophilic sulfate-reducing bacterium Desulfovibrio thermophilus (DSM 1276) and studied by EPR and optical spectroscopic techniques. The visible spectrum of the purified bisulfite reductase exhibits absorption maxima at 578.5, 392.5 and 281 nm with a weak band around 700 nm. Photoreduction of the native enzyme causes a decrease in absorption at 578.5 nm and a concomitant increase in absorption at 607 nm. When reduced, the enzyme reacts with cyanide, sulfite, sulfide and carbon monoxide to give stable complexes. The EPR spectrum of the native D. thermophilus bisulfite reductase shows the presence of a high-spin ferric signal with g values at 7.26, 4.78 and 1.92. Upon photoreduction the high-spin ferric heme signal disappeared and a typical 'g = 1.94' signal of [4Fe-4S] type cluster appeared. Chemical analyses show that the enzyme contains four sirohemes and eight [4Fe-4S] centers per mol of protein. The molecular mass determined by gel filtration was found to be 175 kDa. On SDS-gel electrophoresis the enzyme presents a main band of 44 to 48 kDa. These results suggest that the bisulfite reductase contains probably one siroheme and two [4Fe-4S] centers per monomer. The dissimilatory bisulfite reductase from D. thermophilus presents some homologous properties with desulfofuscidin, the bisulfite reductase isolated from Thermodesulfobacterium commune (Hatchikian, E.C. and Zeikus, J.G. (1983) J. Bacteriol. 153, 1211-1220).

A.G., B.  1990.  Programmable Cardiac Simulator. 2nd Portuguese Congress of Biomedical Engineering. , Aveiro Abstract

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Batista, AG.  1990.  Programmable Cardiac Simulator. Abstract

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Pina, F, Sotomayor J, Moggi L.  1990.  PHOTOCHEMISTRY OF THE CO(SEP)3+-I- SYSTEM - EVALUATION OF THE QUANTUM YIELD FOR THE PHOTOCHEMICAL REDOX REACTION OF THE ION-PAIR. Journal of Photochemistry and Photobiology a-Chemistry. 53:411-422., Number 3 AbstractWebsite
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A.G., B.  1990.  Programmable Cardiac Simulator. 2nd Portuguese Congress of Biomedical Engineering. , Aveiro Abstract
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Batista, AG.  1990.  Programmable Cardiac Simulator. 2nd Portuguese Congress of Biomedical Engineering. Abstract
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1989
Sotomayor, J, Costa JC, Mulazzani QG, Pina F.  1989.  PHOTODECARBOXYLATION OF CITRATE THROUGH ION-PAIR PHOTOCHEMISTRY - THE CO(SEP)3+CITRATE1-, CITRATE2-, CITRATE3- SYSTEM. Journal of Photochemistry and Photobiology a-Chemistry. 49:195-202., Number 1-2 AbstractWebsite
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1988
FIGUEIREDO, P, Pina F.  1988.  A PHOTOCATALYTIC CYCLE FOR MILD OXIDATION BY DIOXYGEN OF SUBSTRATES EASILY OXIDIZABLE BY IODINE. Journal of Photochemistry and Photobiology a-Chemistry. 44:57-61., Number 1 AbstractWebsite
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Pina, F, Maestri M.  1988.  PHOTOCHEMISTRY OF CO(EDTA)–I-SYSTEM IN AQUEOUS-SOLUTIONS. Inorganica Chimica Acta. 142:223-228., Number 2 AbstractWebsite
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1987
Werth, MT, Kurtz DM, Moura I, Legall J.  1987.  Proton NMR spectra of rubredoxins: new resonances assignable to .alpha.-CH and .beta.-CH2 hydrogens of cysteinate ligands to iron(II), 1987/01/01. Journal of the American Chemical Society. 109:273-275., Number 1: American Chemical Society AbstractWebsite
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1986
Czechowski, M, Fauque G, Galliano N, Dimon B, Moura I, Moura JJG, Xavier AV, Barato BAS, Lino AR, Legall J.  1986.  Purification and characterization of three proteins from a halophilic sulfate-reducing bacterium,<i>Desulfovibrio salexigens</i&gt. Journal of Industrial Microbiology & Biotechnology. 1:139-147., Number 3: Springer Berlin / Heidelberg AbstractWebsite
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1984
Fauque, G, Teixeira M, Moura I, Lespinat PA, Xavier AV, Dervartanian DV, Peck, H. D. J, Legall J, Moura JG.  1984.  Purification, characterization and redox properties of hydrogenase from Methanosarcina barkeri (DSM 800), Jul 2. Eur J Biochem. 142:21-8., Number 1 AbstractWebsite

A soluble hydrogenase from the methanogenic bacterium, Methanosarcina barkeri (DSM 800) has been purified to apparent electrophoretic homogeneity, with an overall 550-fold purification, a 45% yield and a final specific activity of 270 mumol H2 evolved min-1 (mg protein)-1. The hydrogenase has a high molecular mass of approximately equal to 800 kDa and subunits with molecular masses of approximately equal to 60 kDa. The enzyme is stable to heating at 65 degrees C and to exposure to air at 4 degrees C in the oxidized state for periods up to a week. The overall stability of this enzyme is compared with other hydrogenase isolated from strict anaerobic sulfate-reducing bacteria. Ms. barkeri hydrogenase shows an absorption spectrum typical of a non-heme iron protein with maxima at 275 nm, 380 nm and 405 nm. A flavin component, identified as FMN or riboflavin was extracted under acidic conditions and quantified to approximately one flavin molecule per subunit. In addition to this component, 8-10 iron atoms and 0.6-0.8 nickel atom were also detected per subunit. The electron paramagnetic resonance (EPR) spectrum of the native enzyme shows a rhombic signal with g values at 2.24, 2.20 and approximately equal to 2.0. probably due to nickel which is optimally measured at 40 K but still detectable at 77 K. In the reduced state, using dithionite or molecular hydrogen as reductants, at least two types of g = 1.94 EPR signals, due to iron-sulfur centers, could be detected and differentiated on the basis of power and temperature dependence. Center I has g values at 2.04, 1.90 and 1.86, while center II has g values at 2.08, 1.93 and 1.85. When the hydrogenase is reduced by hydrogen or dithionite the rhombic EPR species disappears and is replaced by other EPR-active species with g values at 2.33, 2.23, 2.12, 2.09, 2.04 and 2.00. These complex signals may represent different nickel species and are only observable at temperatures higher than 20 K. In the native preparation, at high temperatures (T greater than 35 K) or in partially reduced samples, a free radical due to the flavin moiety is observed. The EPR spectrum of reduced hydrogenase in 80% Me2SO presents an axial type of spectrum only detectable below 30 K.

Calhorda, MJ, Costa SMB, Dias AR, Pina FJS.  1984.  PHOTOCHEMICAL REACTIVITY OF BIS-CYCLOPENTADIENYL METAL-COMPLEXES M(ETA-5-C5H5)2X2 N+(N=0,1 - M=MO, W - X=CL, BR, L). Nouveau Journal De Chimie-New Journal of Chemistry. 8:619-625., Number 10 AbstractWebsite
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1983
Moura, I, Moura JJG, Santos H, Xavier AV, Burch G, Peck Jr HD, Legall J.  1983.  Proteins containing the factor F430 from methanosarcina barkeri and methanobacterium thermoautotrophicum: Isolation and properties. Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology. 742:84-90., Number 1 AbstractWebsite
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1982
Legall, J, Ljungdahl PO, Moura I, Peck, H. D. J, Xavier AV, Moura JJ, Teixera M, Huynh BH, Dervartanian DV.  1982.  The presence of redox-sensitive nickel in the periplasmic hydrogenase from Desulfovibrio gigas, May 31. Biochem Biophys Res Commun. 106:610-6., Number 2 AbstractWebsite
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1981
Costa, SMB, Dias AR, Pina FJS.  1981.  PHOTOSUBSTITUTION REACTIONS OF W(ETA-C5H5)2(CH3)2 PF6 - SOME EVIDENCE FOR AN ALPHA-ELIMINATION MECHANISM. Journal of the Chemical Society-Dalton Transactions. :314-316., Number 1 AbstractWebsite
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1979
Costa, SMB, Dias AR, Pina FJS.  1979.  PHOTOSUBSTITUTION REACTIONS ON DI-ETA-5-CYCLOPENTADIENYL-MOLYBDENUM AND DI-ETA-5-CYCLOPENTADIENYL-TUNGSTEN COMPLEXES. Journal of Organometallic Chemistry. 175:193-204., Number 2 AbstractWebsite
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1976
Bruschi, M, Hatchikian C, Legall J, Moura JJ, Xavier AV.  1976.  Purification, characterization and biological activity of three forms of ferredoxin from the sulfate-reducing bacterium Desulfovibrio gigas, Nov 9. Biochim Biophys Acta. 449:275-84., Number 2 AbstractWebsite

Three forms of ferredoxin FdI, FdI', and FdII have been isolated from Desulfovibrio gigas, a sulfate reducer. They are separated by a combination of DEAE-cellulose and gel filtration chromatographic procedures. FdI and FdI' present a slight difference in isoelectric point which enables the separation of the two forms over DEAE-cellulose, while FdII is easily separated from the two other forms by gel filtration. The three forms have the same amino acid composition and are isolated in different aggregation states. Molecular weight determinations by gel filtration gave values of 18 000 for FdI and FdI' and 24 000 for FdII, whereas a value of 6000 is determined when dissociation is accomplished with sodium dodecyl sulfate. The electronic spectra are different and their ultraviolet-visible absorbance rations are 0.77, 0.87 and 0.68 respectively for FdI, FdI' and FdII. Despite these differences, the physiological activities of the three forms are similar as far as the reduction of sulfite by molecular hydrogen is concerned.

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