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Identification of three classes of hydrogenase in the genus, Desulfovibrio, Prickril, Benet C., He Shao-Hua, Li Ching, Menon Nanda, Choi Eui-Sung, Przybyla Alan E., DerVartanian Daniel V., Peck Jr Harry D., Fauque Guy, Legall Jean, Teixeira Miguel, Moura Isabel, Moura Jose J. G., Patil Daulat, and Huynh Boi H. , Biochemical and Biophysical Research Communications, Volume 149, Number 2, p.369-377, (1987) AbstractWebsite
Imine Ligands Based on Ferrocene: Synthesis, Structural and Mössbauer Characterization and Evaluation as Chromogenic and Electrochemical Sensors for Hg+2, Rosa, V., Gaspari A., Folgosa F., Cordas C. M., Tavares P., Santos-Silva T., Barroso S., and Avilés T. , New J Chem, Volume 42, p.3334-3343, (2018) Website
Immunocytochemical localization of APS reductase and bisulfite reductase in three <i>Desulfovibrio</i> species, Kremer, D. R., Veenhuis M., Fauque G., Peck H. D., Legall J., Lampreia J., Moura J. J. G., and Hansen T. A. , Archives of Microbiology, Volume 150, Number 3, p.296-301, (1988) AbstractWebsite

The localization of APS reductase and bisulfite reductase in Desulfovibrio gigas, D. vulgaris Hildenborough and D. thermophilus was studied by immunoelectron microscopy. Polyclonal antibodies were raised against the purified enzymes from each strain. Cells fixed with formaldehyde/glutaraldehyde were embedded and ultrathin sections were incubated with antibodies and subsequently labeled with protein A-gold. The bisulfite reductase in all three strains and APS reductase in d. gigas and D. vulgaris were found in the cytoplasm. The labeling of d. thermophilus with APS reductase antibodies resulted in a distribution of gold particles over the cytoplasmic membrane region. The localization of the two enzymes is discussed with respect to the mechanism and energetics of dissimilatory sulfate reduction.

Implications of oxidovanadium (IV) binding to actin, Ramos, S., Almeida R. M., Moura J. J., and Aureliano M. , Eur J Inorg Chem, Volume 105, Issue 6, p.777, (2011)
Implications of oxidovanadium(IV) binding to actin, Ramos, S., Almeida R. M., Moura J. J., and Aureliano M. , J Inorg Biochem, Jun, Volume 105, Number 6, p.777-83, (2010) AbstractWebsite

Oxidovanadium(IV), a cationic species (VO(2+)) of vanadium(IV), binds to several proteins, including actin. Upon titration with oxidovanadium(IV), approximately 100% quenching of the intrinsic fluorescence of monomeric actin purified from rabbit skeletal muscle (G-actin) was observed, with a V(50) of 131 muM, whereas for the polymerized form of actin (F-actin) 75% of quenching was obtained and a V(50) value of 320 muM. Stern-Volmer plots were used to estimate an oxidovanadium(IV)-actin dissociation constant, with K(d) of 8.2 muM and 64.1 muM VOSO(4), for G-actin and F-actin, respectively. These studies reveal the presence of a high affinity binding site for oxidovanadium(IV) in actin, producing local conformational changes near the tryptophans most accessible to water in the three-dimensional structure of actin. The actin conformational changes, also confirmed by (1)H NMR, are accompanied by changes in G-actin hydrophobic surface, but not in F-actin. The (1)H NMR spectra of G-actin treated with oxidovanadium(IV) clearly indicates changes in the resonances ascribed to methyl group and aliphatic regions as well as to aromatics and peptide-bond amide region. In parallel, it was verified that oxidovanadium(IV) prevents the G-actin polymerization into F-actin. In the 0-200 muM range, VOSO(4) inhibits 40% of the extent of polymerization with an IC(50) of 15.1 muM, whereas 500 muM VOSO(4) totally suppresses actin polymerization. The data strongly suggest that oxidovanadium(IV) binds to actin at specific binding sites preventing actin polymerization. By affecting actin structure and function, oxidovanadium(IV) might be responsible for many cellular effects described for vanadium.

An improved clean sonoreactor-based method for protein identification by mass spectrometry-based techniques, Santos, H. M., Mota Cristiano, Lodeiro C., Moura Isabel, Isaac Issa, and Capelo J. L. , Talanta, Dec 15, Volume 77, Number 2, p.870-875, (2008) AbstractWebsite

A new clean fast (8 min) method for in-solution protein digestion Without detergent or urea for protein identification by peptide mass fingerprint and mass spectrometry-based techniques is Proposed. The new method avoids the use of time consuming desalting procedures entailing the following four steps done under the effect of an ultrasonic field provided by a sonoreactor: denaturation (1 min) in a mixed Solution of water:acetonitrile 1/1 (v/v): protein reduction (1 min); protein alkylation (1 min); and protein digestion (5 min). Five Proteins with masses comprised between 14.4 kDa and 97 kDa and the protein splitsoret cytochrome c from D. desulfuricans ATCC27774, Were Successfully identified with this procedure. No differences were found in the sequence coverage or in the number of peptides matched when the new clean method was compared to another one using urea. Twofold better signal-to-noise ratios were obtained in the MALDI spectra from protein samples prepared with the new method when comparing it with a method using urea. The new digestion method avoids the need to remove salt content and increases throughput (six samples at once) while reducing sample loss and contamination from sample handling. (C) 2008 Elsevier B.V. All rights reserved.

Improving sample treatment for in-solution protein identification by peptide mass fingerprint using matrix-assisted laser desorption/ionization time-of-flight mass Spectrometry, Santos, H. M., Rial-Otero R., Fernandes L., Vale G., Rivas M. G., Moura I., and Capelo J. L. , Journal of Proteome Research, Sep, Volume 6, Number 9, p.3393-3399, (2007) AbstractWebsite

Three ultrasonic energy sources were studied to speed up the sample treatment for in-solution protein identification by peptide mass fingerprint using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Protein reduction, alkylation, and enzymatic digestion steps were done in 15 min. Nine proteins, including zinc resistance-associated protein precursor from Desulfovibrio desulfuricans strain G20 and split-soret cytochrome c from D. desulfuricans ATCC27774 were successfully identified with the new protocol.

In Situ Electrochemical Characterization of a Microbial Fuel Cell Biocathode Running on Wastewater, Ramanaiah, S. V., Cordas C. M., Matiasand S., and Fonseca L. P. , Catalysts, Volume 11, p.839, (2021)
Incorporation of cytoplasmic vesicles into apical membrane of mammalian urinary bladder epithelium, Lewis, S. A., and de Moura J. L. , Nature, Jun 24, Volume 297, Number 5868, p.685-8, (1982) AbstractWebsite
Incorporation of either molybdenum or tungsten into formate dehydrogenase from Desulfovibrio alaskensis NCIMB 13491; EPR assignment of the proximal iron-sulfur cluster to the pterin cofactor in formate dehydrogenases from sulfate-reducing bacteria, Brondino, C. D., Passeggi M. C., Caldeira J., Almendra M. J., Feio M. J., Moura J. J., and Moura I. , J Biol Inorg Chem, Mar, Volume 9, Number 2, p.145-51, (2004) AbstractWebsite

We report the characterization of the molecular properties and EPR studies of a new formate dehydrogenase (FDH) from the sulfate-reducing organism Desulfovibrio alaskensis NCIMB 13491. FDHs are enzymes that catalyze the two-electron oxidation of formate to carbon dioxide in several aerobic and anaerobic organisms. D. alaskensis FDH is a heterodimeric protein with a molecular weight of 126+/-2 kDa composed of two subunits, alpha=93+/-3 kDa and beta=32+/-2 kDa, which contains 6+/-1 Fe/molecule, 0.4+/-0.1 Mo/molecule, 0.3+/-0.1 W/molecule, and 1.3+/-0.1 guanine monophosphate nucleotides. The UV-vis absorption spectrum of D. alaskensis FDH is typical of an iron-sulfur protein with a broad band around 400 nm. Variable-temperature EPR studies performed on reduced samples of D. alaskensis FDH showed the presence of signals associated with the different paramagnetic centers of D. alaskensis FDH. Three rhombic signals having g-values and relaxation behavior characteristic of [4Fe-4S] clusters were observed in the 5-40 K temperature range. Two EPR signals with all the g-values less than two, which accounted for less than 0.1 spin/protein, typical of mononuclear Mo(V) and W(V), respectively, were observed. The signal associated with the W(V) ion has a larger deviation from the free electron g-value, as expected for tungsten in a d(1) configuration, albeit with an unusual relaxation behavior. The EPR parameters of the Mo(V) signal are within the range of values typically found for the slow-type signal observed in several Mo-containing proteins belonging to the xanthine oxidase family of enzymes. Mo(V) resonances are split at temperatures below 50 K by magnetic coupling with one of the Fe/S clusters. The analysis of the inter-center magnetic interaction allowed us to assign the EPR-distinguishable iron-sulfur clusters with those seen in the crystal structure of a homologous enzyme.

Incorporation of molybdenum in rubredoxin: Models for mononuclear molybdenum enzymes, Maiti, B. K., Maia L. B., Silveira C., Todorovic S., Carreira C., Carepo M., Grazina R., Moura I., and Moura J. J. G. , J Biol Inorg Chem, Volume 20, p.821-829, (2015)
Induced peroxidase activity of haem containing nitrate reductases revealed by protein film electrochemistry, Coelho, C., Marangon J., Rodrigues D., Moura J. J. G., Romão M. J., Paes de Sousa P. M., and Correia dos Santos M. M. , J Electroanal Chem, Volume 693, p.105-113, (2013)
Influence of respiratory substrate in carbon steel corrosion by a sulphate reducing prokaryote model organism, Dall`Agnol, L., Cordas C., and Moura J. J. G. , Bioelectrochemistry, Volume 97, p.43-51, (2014)
Influence of storage solution on enamel demineralization submitted to pH cycling, Moura, J. S., Rodrigues L. K., Del Bel Cury A. A., Lima E. M., and Garcia R. M. , J Appl Oral Sci, Sep, Volume 12, Number 3, p.205-8, (2004) AbstractWebsite

Extracted human teeth are frequently used for research or educational purposes. Therefore, it is necessary to store them in disinfectant solutions that do not alter dental structures. Thus, this study evaluated the influence of storage solution on enamel demineralization. For that purpose, sixty samples were divided into the following groups: enamel stored in formaldehyde (F1), stored in thymol (T1), stored in formaldehyde and submitted to pH cycling (F2), stored in thymol and submitted to pH cycling (T2). All samples were evaluated by cross-sectional microhardness analysis and had their percentage of mineral volume versus micrometer (integrated area) determined. Differences between groups were found up to 30-microm depth from the enamel surface (p < 0.05), where samples from group T2 were more demineralized. It was concluded that the storage solution influenced the reaction of a dental substrate to a cariogenic challenge, suggesting that formaldehyde may increase enamel resistance to demineralization, when compared to demineralization occurring in enamel stored in thymol solution.

Influence of the protein staining in the fast ultrasonic sample treatment for protein identification through peptide mass fingerprint and matrix-assisted laser desorption ionization time of flight mass spectrometry, Galesio, M., Vieira D. V., Rial-Otero R., Lodeiro C., Moura I., and Capelo J. L. , Journal of Proteome Research, May, Volume 7, Number 5, p.2097-2106, (2008) AbstractWebsite

The influence of the protein staining used to visualize protein bands, after in-gel protein separation, for the correct identification of proteins by peptide mass fingerprint (PMF) after application of the ultrasonic in-gel protein protocol was studied. Coomassie brilliant blue and silver nitrate, both visible stains, and the fluorescent dyes Sypro Red and Sypro Orange were evaluated. Results obtained after comparison with the overnight in-gel protocol showed that good results, in terms of protein sequence coverage and number of peptides matched, can be obtained with anyone of the four stains studied. Two minutes of enzymatic digestion time was enough for proteins stained with coomassie blue, while 4 min was necessary when silver or Sypro stainings were employed in order to reach equivalent results to those obtained for the overnigh in-gel protein protocol. For the silver nitrate stain, the concentration of silver present in the staining solution must be 0.09% (w/v) to minimize background in the MALDI mass spectra.

Information from e.p.r. spectroscopy on the iron-sulphur centres of the iron-molybdenum protein (aldehyde oxidoreductase) of Desulfovibrio gigas, Bray, R. C., Turner N. A., Legall J., Barata B. A., and Moura J. J. , Biochem J, Dec 15, Volume 280 ( Pt 3), p.817-20, (1991) AbstractWebsite

E.p.r. spectra of reduced iron-sulphur centres of the aldehyde oxidoreductase (iron-molybdenum protein) of Desulfovibrio gigas were recorded at X-band and Q-band frequencies and simulated. Results are consistent with the view that only two types of [2Fe-2S] clusters are present, as in eukaryotic molybdenum-containing hydroxylases. The data indicate the Fe/SI centre to be very similar, and the Fe/SII centre somewhat similar, to these centres in the eukaryotic enzymes.

Insights into nitrous oxide reductase, Pauleta, S. R., Carreira C., and Moura I. , Metalloenzymes in Denitrification: Applications and Environmental Impacts, RSC Metallobiology Series No. 9 (ISBN: 978-1-78262-376-2)., p.141-169, (2017)
Insights into the electrochemical behaviour of composite materials: Monovacant polyoxometalates porous metal-organic framework, Paes de Sousa, P. M., Grazina R., Barbosa A. D. S., de Castro Baltazar, Moura J. J. G., Cunha-Silva L., and Salete S. , Electrochim Acta, Volume 87, p.853-859, (2013)
Insights into the molybdenum/copper heterometallic cluster assembly in the orange protein: probing intermolecular interactions with an artificial metal-binding ATCUN tag, Maiti, B. K., Almeida R. M., Maia L. B., Moura I., and Moura J. J. G. , Inorg Chem, Volume 56, p.8900-8911, (2017) Website
Insights into the recognition and electron transfer steps in nitric oxide reductase from Marinobacter hydrocarbonoclasticus, Ramos, S., Almeida R. M., Cordas C. M., Moura J. J. G., Pauleta S. R., and Moura I. , J Inorg Biochem, Volume 177, p.402-411, (2017)
Interactions of vanadium(V)-citrate complexes with the sarcoplasmic reticulum calcium pump, Aureliano, M., Tiago T., Gandara R. M., Sousa A., Moderno A., Kaliva M., Salifoglou A., Duarte R. O., and Moura J. J. , J Inorg Biochem, Dec, Volume 99, Number 12, p.2355-61, (2005) AbstractWebsite

Among the biotargets interacting with vanadium is the calcium pump from the sarcoplasmic reticulum (SR). To this end, initial research efforts were launched with two vanadium(V)-citrate complexes, namely (NH(4))(6)[V(2)O(4)(C(6)H(4)O(7))(2)].6H(2)O and (NH(4))(6)[V(2)O(2)(O(2))(2)(C(6)H(4)O(7))(2)].4H(2)O, potentially capable of interacting with the SR calcium pump by combining kinetic studies with (51)V NMR spectroscopy. Upon dissolution in the reaction medium (concentration range: 4-0.5mM), both vanadium(V):citrate (VC) and peroxovanadium(V):citrate (PVC) complexes are partially converted into vanadate oligomers. A 1mM solution of the PVC complex, containing 184microM of the PVC complex, 94microM oxoperoxovanadium(V) (PV) species, 222microM monomeric (V1), 43microM dimeric (V2) and 53microM tetrameric (V4) species, inhibits Ca(2+) accumulation by 75 %, whereas a solution of the VC complex of the same vanadium concentration, containing 98microM of the VC complex, 263microM monomeric (V1), 64microM dimeric (V2) and 92microM tetrameric (V4) species inhibits the calcium pump activity by 33 %. In contrast, a 1 mM metavanadate solution, containing 460microM monomeric (V1), 90.2microM dimeric (V2) and 80microM tetrameric (V4) species, has no effect on Ca(2+) accumulation. The NMR signals from the VC complex (-548.0ppm), PVC complex (-551.5ppm) and PV (-611.1ppm) are broadened upon SR vesicle addition (2.5mg/ml total protein). The relative order for the half width line broadening of the NMR signals, which reflect the interaction with the protein, was found to be V4>PVC>VC>PV>V2=V1=1, with no effect observed for the V1 and V2 signals. Putting it all together the effects of two vanadium(V)-citrate complexes on the modulation of calcium accumulation and ATP hydrolysis by the SR calcium pump reflected the observed variable reactivity into the nature of key species forming upon dissolution of the title complexes in the reaction media.

Interconversion from 3Fe into 4Fe clusters in the presence of Desulfovibrio gigas cell extracts, Moura, J. J., Legall J., and Xavier A. V. , Eur J Biochem, Jun 1, Volume 141, Number 2, p.319-22, (1984) AbstractWebsite

Desulfovibrio gigas ferredoxin II (FdII) contains a single 3Fe cluster [Huynh, B.H., Moura, J.J.G., Moura, I., Kent, T.A., LeGall, J., Xavier, A.V., and Munck, E. (1980) J. Biol. Chem. 255, 3242-3244]. In the oxidized state the protein exhibits an intense electron paramagnetic resonance (EPR) signal at g = 2.02. Upon one-electron reduction the center becomes EPR silent. In the presence of D. gigas crude cell extracts, devoid of acidic electron carriers and supplemented with pyruvate and FdII, an EPR signal typical of reduced [4Fe-4S] centers is obtained. The appearance of this signal correlates with the beginning of stimulation of the phosphoroclastic reaction as judged by the production of H2. These results, supported by the occurrence of easy chemical conversion of the 3Fe cluster of D. gigas ferredoxin into 4Fe structures [Moura, J.J.G., Moura, I., Kent, T.A., Lipscomb, J.D., Huynh, B.H., LeGall, J., Xavier, A.V., and Munch, E. (1982) J. Biol. Chem. 257, 6259-6267], suggest that cluster conversion takes place in conditions close to the situation in vivo. This cluster interconversion is discussed in the context of some of the relevant metabolic pathways of Desulfovibrio spp.

Interconversions of [3Fe-3S] and [4Fe-4S] clusters. Mossbauer and electron paramagnetic resonance studies of Desulfovibrio gigas ferredoxin II, Moura, J. J., Moura I., Kent T. A., Lipscomb J. D., Huynh B. H., Legall J., Xavier A. V., and Munck E. , J Biol Chem, Jun 10, Volume 257, Number 11, p.6259-67, (1982) AbstractWebsite
Iron compounds after erythrophagocytosis: chemical characterization and immunomodulatory effects, Costa, L. M., Moura E. M., Moura J. J., and de Sousa M. , Biochem Biophys Res Commun, Jun 9, Volume 247, Number 1, p.159-65, (1998) AbstractWebsite

In humans, the lymphomyeloid system has a fundamental role on iron metabolism promoting its recycling due to a continuous removal of effete red blood cells. Additionally, one of the most intriguing aspects of metalloporphyrins in biology is their effect on the immune system. However, the process of erythrocyte catabolism is still poorly understood and needs further research. In the present study, we attempt to investigate the nature and the possible physiologic role of Fe compounds released after erythrophagocytosis during the removal of red blood cells. Monocyte erythrophagocytosis in vitro experiments were done to characterize chemically the Fe compounds present inside the cells and in the culture supernatants. We tested the probable immunomodulatory functions of erythrophagocytosis products over lymphocyte cultures activated in vitro with T mitogens (alpha-CD3). Data obtained from atomic absorption spectroscopy confirmed the presence of Fe in the culture supernatants of monocyte cultures after erythrophagocytosis. Also, high-spin haem complexes derived from erythrocyte catabolism were detected by electron paramagnetic electronic resonance. Finally, in vitro activated lymphocyte proliferation experiments indicate the co-mitogenic properties of monocyte culture supernatants after red blood cells phagocytosis. Thus, the results of the present work provide evidence that culture monocyte supernatants after in vitro erythrophagocytosis contain Fe (III) high-spin haem complexes and show lymphocyte proliferation co-stimulatory properties.

The iron-sulfur centers of the soluble [NiFeSe] hydrogenase, from Desulfovibrio baculatus (DSM 1743). EPR and Mossbauer characterization, Teixeira, M., Moura I., Fauque G., Dervartanian D. V., Legall J., Peck, H. D. Jr., Moura J. J., and Huynh B. H. , Eur J Biochem, Apr 30, Volume 189, Number 2, p.381-6, (1990) AbstractWebsite

The soluble (cytoplasmic plus periplasmic) Ni/Fe-S/Se-containing hydrogenase from Desulfovibrio baculatus (DSM 1743) was purified from cells grown in an 57Fe-enriched medium, and its iron-sulfur centers were extensively characterized by Mossbauer and EPR spectroscopies. The data analysis excludes the presence of a [3Fe-4S] center, either in the native (as isolated) or in the hydrogen-reduced states. In the native state, the non-heme iron atoms are arranged as two diamagnetic [4Fe-4S]2+ centers. Upon reduction, these two centers exhibit distinct and unusual Mossbauer spectroscopic parameters. The centers were found to have similar mid-point potentials (approximately -315 mV) as determined by oxidation-reduction titratins followed by EPR.