Pina, F, Parola AJ.
1999.
Photochemistry of supramolecular species involving anionic coordination compounds and polyammonium macrocyclic receptors, 1999. Coordination Chemistry Reviews. 185-6:149-165.
AbstractPolyammonium macrocyclic receptors can bind anionic coordination compounds, namely those containing cyanide ligands. The;driving force to maintain the adduct is essentially the coulombic attraction, but the possibility of formation of hydrogen bonds is also important to define the geometry of the structure. The second coordination sphere that results from the binding of the polyammonium macrocycle can change several physicochemical properties of the metal coordination-compound, such as spectroscopic, redox and photophysical properties as well as the photochemical reactivity. These. changes permit:to infer, in some favourable cases, details of the supramolecular structure in solution. (C) 1999 Elsevier Science S.A. All rights reserved.
Kuhn, FE, Goncalves IS, Lopes AD, Lopes JP, Romao CC, Wachter W, Mink J, Hajba L, Parola AJ, Pina F, Sotomayor J.
1999.
Tetracarboxylatodirhenium complexes linked by axial cyano bridges to metalpentacarbonyl ligands - Synthesis and characterization, 1999. European Journal of Inorganic Chemistry. :295-301.
AbstractReaction of Re-2{mu-O2CC(CH3)(3)}(4)Cl-2 with [(CO)(5)M-CN]Na (M = Cr, Mo, W) leads to tetranuclear complexes of formula Re-2{mu-O2CC(CH3)(3)}(4)[-NC-M(CO)(5)](2) (M = Cr, Mo, W). These complexes were characterized by H-1-, C-13-, and Mo-95-NMR, IR and Raman spectroscopy, elemental analysis and examined by cyclic voltammetry. The applied methods show the donor capabilities of the [(CO)(5)M-CN](-) ligands which shift electron density towards the Re centers weakening the Re-Re quadruple bond. The Re-Re bond lengths and the v(Re-Re) force constants are estimated based on the FT-IR and Raman examinations. Photochemical examinations and TG/MS experiments have also been conducted. The latter methods shows that the product complexes decompose around 100 degrees C, by first loosing their carbonyl substituents; as do the Cr, Mo, W precursor compounds. The dirhenium tetrapivalate unit decomposes only at higher temperatures in a distinct second step.
de Lencastre, H, Wu SW, Pinho MG, Ludovice AM, Filipe S, Gardete S, Sobral R, Gill S, Chung M, Tomasz A.
1999.
Antibiotic resistance as a stress response: complete sequencing of a large number of chromosomal loci in Staphylococcus aureus strain COL that impact on the expression of resistance to methicillin. Microb. Drug Resist. 5:163-175.
Pereira, AS, Tavares P, Krebs C, Huynh BH, Rusnak F, Moura I, Moura JJG.
1999.
Biochemical and spectroscopic characterization of overexpressed fuscoredoxin from Escherichia coli. Biochemical And Biophysical Research Communications. {260}:{209-215}., Number {1}
AbstractFuscoredoxin is a unique iron containing protein of yet unknown function originally discovered in the sulfate reducers of the genus Desulfovibrio. It contains two iron-sulfur clusters: a cubane [4Fe-4S] and a mixed oxo- and sulfide-bridged 4Fe cluster of unprecedented structure. The recent determination of the genomic sequence of Escherichia coli (E. coli) has revealed a homologue of fuscoredoxin in this facultative microbe. The presence of this gene in E. coli raises interesting questions regarding the function of fuscoredoxin and whether this gene represents a structural homologue of the better-characterized Desulfovibrio proteins. In order to explore the latter, an overexpression system for the E. coli fuscoredoxin gene was devised. The gene was cloned from genomic DNA by use of the polymerase chain reaction into the expression vector pT7-7 and overexpressed in E. coli BL21(DE3) cells. After two chromatographic steps a good yield of recombinant protein was obtained (approximately 4 mg of pure protein per liter of culture). The purified protein exhibits an optical spectrum characteristic of the homologue from D. desulfuricans, indicating that cofactor assembly was accomplished. Iron analysis indicated that the protein contains circa 8 iron atoms/molecule which were shown by EPR and Mossbauer spectroscopies to be present as two multinuclear clusters, albeit with slightly altered spectroscopic features. A comparison of the primary sequences of fuscoredoxins is presented and differences on cluster coordination modes are discussed on the light of the spectroscopic data. (C) 1999 Academic Press.
Bursakov, SA, Brondino C, Dias JM, Carneiro C, Caldeira J, Duarte RO, Romao MJ, Moura I, Moura JJG.
1999.
Cross immunological reactions and spectroscopy study within nitrate reductase and other mononuclear Mo containing enzymes of the sulfate reducing bacteria. Journal of Inorganic Biochemistry. 74:86-86., Number 1-4
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Dias, JM, Than ME, Humm A, Huber R, Bourenkov GP, Bartunik HD, Bursakov S, Calvete J, Caldeira J, Carneiro C, Moura JJG, Moura I, Romao MJ.
1999.
Crystal structure of the first dissimilatory nitrate reductase at 1.9 angstrom solved by MAD methods. Structure with Folding & Design. 7:65-79., Number 1
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Dias, JM, Than ME, Huber R, Bourenkov GP, Bartunik HD, Bursakov S, Moura JJG, Moura I, Romao MJ.
1999.
Crystallographic studies of a dissimilatory nitrate reductase and mechanistic implications. Journal of Inorganic Biochemistry. 74:113-113., Number 1-4
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Teixeira, S, Dias JM, Carvalho AL, Bourenkov G, Bartunik H, Almendra MJ, Moura I, Moura JJG, Romao MJ.
1999.
Crystallographic studies on a tungsten-containning formate dehydrogenase from Desulfovibrio gigas. Journal of Inorganic Biochemistry. 74:89-89., Number 1-4
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Romao, MJ, Carvalho AL, Dias JM, Teixeira S, Bourenkov G, Bartunik H, Huber R, Maia L, Mira L.
1999.
Preliminary crystallographic studies of xanthine oxidase purified from rat liver. Journal of Inorganic Biochemistry. 74:281-281., Number 1-4
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