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

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A.G., B.  1990.  Programmable Cardiac Simulator. 2nd Portuguese Congress of Biomedical Engineering. , Aveiro Abstract
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1988
Fauque, G, Peck, H. D. J, Moura JJ, Huynh BH, Berlier Y, Dervartanian DV, Teixeira M, Przybyla AE, Lespinat PA, Moura I,, et al.  1988.  The three classes of hydrogenases from sulfate-reducing bacteria of the genus Desulfovibrio, Dec. FEMS Microbiol Rev. 4:299-344., Number 4 AbstractWebsite

Three types of hydrogenases have been isolated from the sulfate-reducing bacteria of the genus Desulfovibrio. They differ in their subunit and metal compositions, physico-chemical characteristics, amino acid sequences, immunological reactivities, gene structures and their catalytic properties. Broadly, the hydrogenases can be considered as 'iron only' hydrogenases and nickel-containing hydrogenases. The iron-sulfur-containing hydrogenase ([Fe] hydrogenase) contains two ferredoxin-type (4Fe-4S) clusters and an atypical iron-sulfur center believed to be involved in the activation of H2. The [Fe] hydrogenase has the highest specific activity in the evolution and consumption of hydrogen and in the proton-deuterium exchange reaction and this enzyme is the most sensitive to CO and NO2-. It is not present in all species of Desulfovibrio. The nickel-(iron-sulfur)-containing hydrogenases [( NiFe] hydrogenases) possess two (4Fe-4S) centers and one (3Fe-xS) cluster in addition to nickel and have been found in all species of Desulfovibrio so far investigated. The redox active nickel is ligated by at least two cysteinyl thiolate residues and the [NiFe] hydrogenases are particularly resistant to inhibitors such as CO and NO2-. The genes encoding the large and small subunits of a periplasmic and a membrane-bound species of the [NiFe] hydrogenase have been cloned in Escherichia (E.) coli and sequenced. Their derived amino acid sequences exhibit a high degree of homology (70%); however, they show no obvious metal-binding sites or homology with the derived amino acid sequence of the [Fe] hydrogenase. The third class is represented by the nickel-(iron-sulfur)-selenium-containing hydrogenases [( NiFe-Se] hydrogenases) which contain nickel and selenium in equimolecular amounts plus (4Fe-4S) centers and are only found in some species of Desulfovibrio. The genes encoding the large and small subunits of the periplasmic hydrogenase from Desulfovibrio (D.) baculatus (DSM 1743) have been cloned in E. coli and sequenced. The derived amino acid sequence exhibits homology (40%) with the sequence of the [NiFe] hydrogenase and the carboxy-terminus of the gene for the large subunit contains a codon (TGA) for selenocysteine in a position homologous to a codon (TGC) for cysteine in the large subunit of the [NiFe] hydrogenase. EXAFS and EPR studies with the 77Se-enriched D. baculatus hydrogenase indicate that selenium is a ligand to nickel and suggest that the redox active nickel is ligated by at least two cysteinyl thiolate and one selenocysteine selenolate residues.(ABSTRACT TRUNCATED AT 400 WORDS)

Teixeira, G, Aviles T, Dias AR, Pina F.  1988.  A KINETIC-STUDY OF PHOTOSUBSTITUTION OF CARBON-MONOXIDE AND TRIPHENYLPHOSPHINE IN COMPLEXES MN(ETA-5-CH3C5H4)(CO)3-N(PPH3)N (N=0, 1 AND 2). Journal of Organometallic Chemistry. 353:83-91., Number 1 AbstractWebsite
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1982
Antonio, MR, Averill BA, Moura I, Moura JJ, Orme-Johnson WH, Teo BK, Xavier AV.  1982.  Core dimensions in the 3Fe cluster of Desulfovibrio gigas ferredoxin II by extended X-ray absorption fine structure spectroscopy, Jun 25. J Biol Chem. 257:6646-9., Number 12 AbstractWebsite

We have obtained the iron K-edge extended X-ray adsorption fine structure spectra of the 3Fe ferredoxin II of Desulfovibrio gigas in the oxidized and reduced states. For both states, interpretation of the EXAFS data suggests that the Fe-S first shell coordination distance is near 2.25 A, in agreement with crystallographic studies of model compounds and proteins containing 2Fe-2S and 4Fe-4S centers, as well as with a recent crystallographic study of Azotobacter vinelandii ferredoxin I (Ghosh, D., Furey, W., Jr., O'Donnell, S., and Stout, C. D. (1981) J. Biol. Chem. 256, 4185-4192). The apparent Fe-Fe distance we obtain for the desulfovibrio protein (2.7 A) also agrees with similar distances seen in other Fe-S centers, except with the 3Fe cluster in the Azotobacter vinelandii ferredoxin I structure, for which an Fe-Fe distance of 4.2 A was reported. We conclude that either the two 3Fe ferredoxins have substantially different core dimensions, a possibility apparently unique to 3Fe centers among known Fe-S systems in proteins, or that one (or more) of the structural studies is in substantial error.

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