86 resultados para EPR spectral studies.


Relevância:

90.00% 90.00%

Publicador:

Resumo:

J Biol Inorg Chem (2007) 12:353–366 DOI 10.1007/s00775-006-0191-9

Relevância:

80.00% 80.00%

Publicador:

Resumo:

J Biol Inorg Chem (2007) 12:777–787 DOI 10.1007/s00775-007-0229-7

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Acc. Chem. Res., 2006, 39 (10), pp 788–796 DOI: 10.1021/ar050104k

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Dissertação apresentada para obtenção do Grau de Doutor em Bioquímica, ramo de Bioquímica-Física, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Dissertação apresentada para obtenção do grau de Doutor em Bioquímica, especialidade Bioquímica-Física, pela Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A novel two-component enzyme system from Escherichia coli involving a flavorubredoxin (FlRd) and its reductase was studied in terms of spectroscopic, redox, and biochemical properties of its constituents. FlRd contains one FMN and one rubredoxin (Rd) center per monomer. To assess the role of the Rd domain, FlRd and a truncated form lacking the Rd domain (FlRd¢Rd), were characterized. FlRd contains 2.9 ( 0.5 iron atoms/subunit, whereas FlRd¢Rd contains 2.1 ( 0.6 iron atoms/subunit. While for FlRd one iron atom corresponds to the Rd center, the other two irons, also present in FlRd¢Rd, are most probably due to a di-iron site. Redox titrations of FlRd using EPR and visible spectroscopies allowed us to determine that the Rd site has a reduction potential of -140 ( 15 mV, whereas the FMN undergoes reduction via a red-semiquinone, at -140 ( 15 mV (Flox/Flsq) and -180 ( 15 mV (Flsq/Flred), at pH 7.6. The Rd site has the lowest potential ever reported for a Rd center, which may be correlated with specific amino acid substitutions close to both cysteine clusters. The gene adjacent to that encoding FlRd was found to code for an FAD-containing protein, (flavo)rubredoxin reductase (FlRd-reductase), which is capable of mediating electron transfer from NADH to DesulfoVibrio gigas Rd as well as to E. coli FlRd. Furthermore, electron donation was found to proceed through the Rd domain of FlRd as the Rd-truncated protein does not react with FlRd-reductase. In vitro, this pathway links NADH oxidation with dioxygen reduction. The possible function of this chain is discussed considering the presence of FlRd homologues in all known genomes of anaerobes and facultative aerobes.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A thesis submitted in fulfilment of the requirements for the degree of Masters in Molecular Genetics and Biomedicine

Relevância:

30.00% 30.00%

Publicador:

Resumo:

J Biol Inorg Chem (2006) 11: 609–616 DOI 10.1007/s00775-006-0110-0

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Middle and Upper Jurassique limestones investigated were sub-divided into nine microfacies (MF) types. The firsts four represent Bathonian sediments with shallow water characteristics typical for carbonate platforms. They are comparable with Wilson's facies zones 6 to 8. Reef and reef debris, near-shore clastic-dominated limestones are not present. These MF-types are reiterated several times without cyclicity. The vertical development of the differentiated facies units indicates a close interfingering. The microfacies data are typical of inter to shallow subtidal environments; both authigenous quartz and low faunal and floral diversity of several layers point to temporary restricted conditions. The occurrence of Dictyoconus cayeuxi LUCAS and Callovian ammonites from the above lying strata argue for a Bathonian age. The MF-types 5-9 (Oxfordian-Kimmeridgian) show completely different sedimentation conditions. Fully marine nearshore recifal limestones alternate with pelagic sediments formed at deeper shelf areas. The pelagic micritic limestones of Oxfordian age are characterized by allodapic intercalations whereas the Oxfordian/Kimmeridgian limestones with tuberolithic fabrics often show intensive silifications. Only initial patch reef growth-stages were reached during the development of the Oxfordian and Kimmeridgian shallow water limestones.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Protein Science (2002), 11:2464–2470