@booklet {4544, year = {Submitted}, note = {n/a}, abstract = {n/a} } @inbook {15864, title = {2.06 - Iron-sulfur clusters {\textendash} functions of an ancient metal site}, booktitle = {Reference Module in Chemistry, Molecular Sciences and Chemical Engineering}, year = {2023}, note = {

n/a

}, month = {2022}, publisher = {Elsevier}, organization = {Elsevier}, abstract = {

Iron-sulfur clusters are ubiquitous and ancient prosthetic groups that are present in all kingdoms of life. In the 1960s, they were recognized to play a role in electron-transfer reactions, but since then several other functions were identified, which can be attributed to their flexible coordination and redox properties. In here, the canonical iron-sulfur clusters, as well as the ones with other coordinating ligands will be described. The chapter has also been updated to account for the advances in the knowledge of complex iron-sulfur clusters of nitrogenase and hydrogenases. In addition, the role of iron-sulfur clusters in metabolic regulation, as sensors of gases (nitric oxide, oxygen), iron and cellular content of iron-sulfur clusters, cellular redox status, and redox cycling compounds, as well as their role in DNA processing enzymes, and their involvement in catalysis of a wide range of reactions will be described. Iron-sulfur clusters also participate in their biosynthetic and repair pathways. The knowledge in this field as evolved tremendously in recent years, which would require a complete chapter devoted to it by itself, reason why the authors have decided not to include this subject in this chapter. The chapter is an update of the one published in the previous edition, focusing on the recent advances mostly on the iron-sulfur clusters involved in new catalytic functions, sensor mechanisms and DNA processing.

}, keywords = {Catalytic iron-sulfur cluster, DNA repair, electron-transfer, GAF domain, Heterometallic cluster, Hydrogenase, Iron homeostasis, Iron-sulfur cluster, Nitrogenase, Non-redox catalysis, Organometallic cluster, PAS domain, SAM-dependent enzyme, Transcription regulator}, isbn = {978-0-12-409547-2}, url = {https://www.sciencedirect.com/science/article/pii/B9780128231449001163}, author = {Pauleta, Sofia R and Grazina, Raquel and Carepo, Marta S P and Moura, Jos{\'e} J. G. and Moura, Isabel} } @article {15865, title = {Biochemical characterization of AniA from Neisseria gonorrhoeae}, journal = {bioRxiv}, year = {2022}, note = {

n/a

}, month = {2022/01/01}, pages = {2022.04.07.487406}, abstract = {

AniA, the nitrite reductase from Neisseria gonorrhoeae, has been shown to play a crucial role in the infection mechanism of this microorganism by producing NO and abolishing epithelial exfoliation. This enzyme is a trimer with one type-1 copper center per subunit and one type 2 copper center in the subunits interface, with the latter being the catalytic site. The two centers were characterized by visible, EPR and CD spectroscopy for the first time, indicating that AniA{\textquoteright}s type 1 copper center has a high rhombicity, which is attributed to its tetrahedral geometry, and shorter Met-Cu bond, while type 2 copper center has the usual properties, though with a shorter hyperfine coupling constant (A//= 9.1 mT). The thermostability of AniA was analyzed by differential scanning calorimetry showing a single endothermic transition in the thermogram, with a maximum at 95 {\textdegree}C, while the CD spectra in the visible region indicates the presence of copper centers at 85-90 {\textdegree}C. The reoxidation rates of AniA in the presence of nitrite were analyzed by visible spectroscopy showing a pH dependence and being higher at pH 6.0. The high thermostability of this enzyme might be important for maintaining a high activity in the extracellular space and be less prone to denaturation and proteolysis, contributing to the proliferation of N. gonorrhoeae.Competing Interest StatementThe authors have declared no competing interest.

}, url = {http://biorxiv.org/content/early/2022/04/07/2022.04.07.487406.abstract}, attachments = {https://docentes.fct.unl.pt/sites/default/files/srp/files/preprint_sp_1.pdf}, author = {Barreiro, Daniela S. and Oliveira, Ricardo N. S. and Pauleta, Sofia R} } @article {15871, title = {Photomodulation of ultrastable host{\textendash}guest complexes in water and their application in light-controlled steroid release}, journal = {Organic Chemistry Frontiers}, volume = {9}, year = {2022}, note = {n/a}, month = {2022}, pages = {4238 - 4249}, publisher = {The Royal Society of Chemistry}, abstract = {

The cucurbit[8]uril (CB8) synthetic receptor is shown to form high-affinity host{\textendash}guest complexes with dicationic dithienylethene (DTE) photoswitches in water. ITC experiments combined with computational studies suggest that the formation of the inclusion complexes is mainly driven by a combination of hydrophobic effects, ion{\textendash}dipole, hydrogen- and chalcogen-bonding interactions. The binding affinities were observed to be much higher for the DTE closed isomers, reaching values in the picomolar range (up to 1011 M-1) while the open isomers display up to 10 000-fold lower affinities, setting ideal conditions for the development of robust photoswitchable host{\textendash}guest complexes. The light-responsive affinity of these photoswitches toward CB8 was explored to control the encapsulation and release of nanomolar affinity steroids via competitive guest replacement.

}, url = {http://dx.doi.org/10.1039/D2QO00423B}, author = {Patr{\'\i}cia M{\'a}ximo and Cola{\c c}o, Miriam and Pauleta, Sofia R and Costa, Paulo J. and Pischel, Uwe and Parola, A Jorge and Bas{\'\i}lio, Nuno} } @article {15869, title = {OrpR is a σ54-dependent activator using an iron-sulfur cluster for redox sensing in Desulfovibrio vulgaris Hildenborough}, journal = {Molecular MicrobiologyMolecular Microbiology}, volume = {116}, year = {2021}, note = {

https://doi.org/10.1111/mmi.14705

}, month = {2021}, pages = {231 - 244}, publisher = {John Wiley \& Sons, Ltd}, abstract = {

Abstract Enhancer binding proteins (EBPs) are key players of σ54-regulation that control transcription in response to environmental signals. In the anaerobic microorganism Desulfovibrio vulgaris Hildenborough (DvH), orp operons have been previously shown to be coregulated by σ54-RNA polymerase, the integration host factor IHF and a cognate EBP, OrpR. In this study, ChIP-seq experiments indicated that the OrpR regulon consists of only the two divergent orp operons. In vivo data revealed that (i) OrpR is absolutely required for orp operons transcription, (ii) under anaerobic conditions, OrpR binds on the two dedicated DNA binding sites and leads to high expression levels of the orp operons, (iii) increasing the redox potential of the medium leads to a drastic down-regulation of the orp operons expression. Moreover, combining functional and biophysical studies on the anaerobically purified OrpR leads us to propose that OrpR senses redox potential variations via a redox-sensitive [4Fe?4S]2+ cluster in the sensory PAS domain. Overall, the study herein presents the first characterization of a new Fe?S redox regulator belonging to the σ54-dependent transcriptional regulator family probably advantageously selected by cells adapted to the anaerobic lifestyle to monitor redox stress conditions.

}, keywords = {anaerobes, Desulfovibrio, enhancer binding protein, iron-sulfur protein, redox sensor, transcriptional regulator}, isbn = {0950-382X}, url = {https://doi.org/10.1111/mmi.14705}, author = {Fi{\'e}vet, Anouchka and Merrouch, Meriem and Brasseur, Ga{\"e}l and Eve, Dana{\'e} and Biondi, Emanuele G. and Valette, Odile and Pauleta, Sofia R and Dolla, Alain and Dermoun, Zorah and Burlat, B{\'e}n{\'e}dicte and Aubert, Corinne} } @article {15868, title = {Acrylamide-hemoglobin adduct: A spectroscopic study}, volume = {241}, year = {2020}, note = {n/a}, month = {2020}, pages = {118644}, abstract = {

Acrylamide is a neurotoxic and carcinogenic organic compound that is able to bind to several biomolecules and form adducts, through nucleophilic addition and in vivo by the Maillard Reaction, interfering with the biological functions of these molecules. Hemoglobin is one of the most abundant intracellular blood proteins, and thus it is of high interest to understand whether the binding of acrylamide can alter its properties. The interaction of acrylamide with hemoglobin was assessed in a 20:1 ratio, and after a 72~h-incubation period, a decrease of ca. 50\% in the absorbance of the hemoglobin{\textquoteright}s Soret band was observed at 37~{\textdegree}C. This together with the analysis of circular dichroism spectra indicate that acrylamide binds in close proximity to the heme group. These perturbations were confirmed to not correspond to the loss of the heme group and were mostly reverted after passing the protein through a size-exclusion chromatographic matrix, suggesting a dominant non-covalent interaction for the observed effect. The thermodynamic parameters of unfolding in the absence and presence of acrylamide, suggest an interaction based on H-bonds and van der Waals forces that slightly stabilizes hemoglobin. The oxygen binding capacity of hemoglobin does not seem to be hindered, as no differences in the Q bands were observed in the adduct.

}, keywords = {Acrylamide adduct, Circular dichroism, Hemoglobin, Thermal stability, Visible spectroscopy}, isbn = {1386-1425}, url = {https://www.sciencedirect.com/science/article/pii/S1386142520306235}, author = {Favinha, Andr{\'e} G. and Barreiro, Daniela S. and Martins, Joana N. and O{\textquoteright}Toole, Philip and Pauleta, Sofia R} } @article {15867, title = {The effect of pH on Marinobacter hydrocarbonoclasticus denitrification pathway and nitrous oxide reductase}, volume = {25}, year = {2020}, note = {n/a}, month = {2020}, pages = {927 - 940}, abstract = {

Increasing atmospheric concentration of N2O has been a concern, as it is a potent greenhouse gas and promotes ozone layer destruction. In the N-cycle, release of N2O is boosted upon a drop of pH in the environment. Here, Marinobacter hydrocarbonoclasticus was grown in batch mode in the presence of nitrate, to study the effect of pH in the denitrification pathway by gene expression profiling, quantification of nitrate and nitrite, and evaluating the ability of whole cells to reduce NO and N2O. At pH 6.5, accumulation of nitrite in the medium occurs and the cells were unable to reduce N2O. In addition, the biochemical properties of N2O reductase isolated from cells grown at pH 6.5, 7.5 and 8.5 were compared for the first time. The amount of this enzyme at acidic pH was lower than that at pH 7.5 and 8.5, pinpointing to a post-transcriptional regulation, though pH did not affect gene expression of N2O reductase accessory genes. N2O reductase isolated from cells grown at pH 6.5 has its catalytic center mainly as CuZ(4Cu1S), while that from cells grown at pH 7.5 or 8.5 has it as CuZ(4Cu2S). This study evidences that an in vivo secondary level of regulation is required to maintain N2O reductase in an active state.

}, isbn = {1432-1327}, url = {https://doi.org/10.1007/s00775-020-01812-0}, author = {Carreira, C{\'\i}ntia and Nunes, Rute F. and Mestre, Olga and Moura, Isabel and Pauleta, Sofia R} } @article {15866, title = {Proton-coupled electron transfer mechanisms of the copper centres of nitrous oxide reductase from Marinobacter hydrocarbonoclasticus {\textendash} An electrochemical study}, volume = {133}, year = {2020}, note = {n/a}, month = {2020}, pages = {107483}, abstract = {

Reduction of N2O to N2 is catalysed by nitrous oxide reductase in the last step of the denitrification pathway. This multicopper enzyme has an electron transferring centre, CuA, and a tetranuclear copper-sulfide catalytic centre, {\textquotedblleft}CuZ{\textquotedblright}, which exists as CuZ*(4Cu1S) or CuZ(4Cu2S). The redox behaviour of these metal centres in Marinobacter hydrocarbonoclasticus nitrous oxide reductase was investigated by potentiometry and for the first time by direct electrochemistry. The reduction potential of CuA and CuZ(4Cu2S) was estimated by potentiometry to be +275~{\textpm}~5~mV and +65~{\textpm}~5~mV vs SHE, respectively, at pH 7.6. A proton-coupled electron transfer mechanism governs CuZ(4Cu2S) reduction potential, due to the protonation/deprotonation of Lys397 with a pKox of 6.0~{\textpm}~0.1 and a pKred of 9.2~{\textpm}~0.1. The reduction potential of CuA, in enzyme samples with CuZ*(4Cu1S), is controlled by protonation of the coordinating histidine residues in a two-proton coupled electron transfer process. In the cyclic voltammograms, two redox pairs were identified corresponding to CuA and CuZ(4Cu2S), with no additional signals being detected that could be attributed to CuZ*(4Cu1S). However, an enhanced cathodic signal for the activated enzyme was observed under turnover conditions, which is explained by the binding of nitrous oxide to CuZ0(4Cu1S), an intermediate species in the catalytic cycle.

}, keywords = {CuA centre, CuZ centre, Direct electrochemistry, Nitrous oxide reductase, Potentiometry, Proton-coupled electron transfer}, isbn = {1567-5394}, url = {https://www.sciencedirect.com/science/article/pii/S1567539419308813}, author = {Carreira, C{\'\i}ntia and dos Santos, Margarida M.C. and Pauleta, Sofia R and Moura, Isabel} } @inbook {15870, title = {Transition Metals and Sulfur {\textendash} A Strong Relationship for Life5. The Tetranuclear Copper-Sulfide Center of Nitrous Oxide Reductase}, year = {2020}, note = {n/a}, month = {2020}, pages = {139 - 164}, publisher = {De Gruyter}, organization = {De Gruyter}, abstract = {n/a}, url = {https://doi.org/10.1515/9783110589757-011}, author = {Pauleta, Sofia R and Carepo, Marta S P and Moura, Isabel}, editor = {Sosa Torres, Martha and Kroneck, Peter} } @article {13506, title = {The bacterial MrpORP is a novel Mrp/NBP35 protein involved in iron-sulfur biogenesis}, journal = {Scientific Reports}, volume = {9}, year = {2019}, note = {

Export Date: 26 November 2019

}, month = {2019}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85060516481\&doi=10.1038\%2fs41598-018-37021-8\&partnerID=40\&md5=969c40b58a1e37adf72819252ed605d3}, author = {Pardoux, R. and Fi{\'e}vet, A. and Carreira, C. and Brochier-Armanet, C. and Valette, O. and Dermoun, Z. and Py, B. and Dolla, A. and Pauleta, S. R. and Aubert, C.} } @book {13508, title = {Reduction of hydrogen peroxide in gram-negative bacteria {\textendash} bacterial peroxidases}, series = {Advances in Microbial Physiology}, volume = {74}, year = {2019}, note = {

Export Date: 26 November 2019

}, month = {2019}, pages = {415 - 464}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85063953057\&doi=10.1016\%2fbs.ampbs.2019.02.006\&partnerID=40\&md5=9495b8a368926273edeec5d3627aa486}, author = {N{\'o}brega, C. S. and Pauleta, S. R.} } @article {13507, title = {Source and reduction of nitrous oxide}, journal = {Coordination Chemistry Reviews}, volume = {387}, year = {2019}, note = {

Cited By :4Export Date: 26 November 2019

}, month = {2019}, pages = {436 - 449}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85062717693\&doi=10.1016\%2fj.ccr.2019.02.005\&partnerID=40\&md5=82b60d8a054edca473ed2e57fc3160f3}, author = {Pauleta, S. R. and Carepo, M. S. P. and Moura, I} } @article {13511, title = {Genomic organization, gene expression and activity profile of Marinobacter hydrocarbonoclasticus denitrification enzymes}, journal = {PeerJ}, volume = {2018}, year = {2018}, note = {

Export Date: 26 November 2019

}, month = {2018}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85054643371\&doi=10.7717\%2fpeerj.5603\&partnerID=40\&md5=d2d42856fcbc791e4d7b0f5ecc1ce269}, author = {Carreira, C. and Mestre, O. and Nunes, R. F. and Moura, I and Pauleta, S. R.} } @article {13510, title = {Interaction between Neisseria gonorrhoeae bacterial peroxidase and its electron donor, the lipid-modified azurin}, journal = {FEBS Letters}, volume = {592}, year = {2018}, note = {

Cited By :2Export Date: 26 November 2019

}, month = {2018}, pages = {1473 - 1483}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85046010166\&doi=10.1002\%2f1873-3468.13053\&partnerID=40\&md5=31c12e44e362808e4ea432218ad52d32}, author = {N{\'o}brega, C. S. and Pauleta, S. R.} } @article {13509, title = {YhjA - An Escherichia coli trihemic enzyme with quinol peroxidase activity}, journal = {Biochimica et Biophysica Acta - Bioenergetics}, volume = {1859}, year = {2018}, note = {

Cited By :3Export Date: 26 November 2019

}, month = {2018}, pages = {411 - 422}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85044124183\&doi=10.1016\%2fj.bbabio.2018.03.008\&partnerID=40\&md5=4250b14dba59821f3f53859b167cacf9}, author = {N{\'o}brega, C. S. and Devreese, B and Pauleta, S. R.} } @article {10100, title = {Protein-Assisted Formation of Molybdenum Heterometallic Clusters: Evidence for the Formation of S2MoS2-M-S2MoS2 Clusters with M = Fe, Co, Ni, Cu, or Cd within the Orange Protein}, journal = {Inorg Chem}, year = {2017}, note = {

Maiti, Biplab KMaia, Luisa BPauleta, Sofia RMoura, IsabelMoura, Jose J GUnited StatesInorganic chemistryInorg Chem. 2017 Jan 27. doi: 10.1021/acs.inorgchem.6b02906.

}, month = {Jan 27}, edition = {2017/01/28}, abstract = {

The Orange Protein (ORP) is a small bacterial protein, of unknown function, that harbors a unique molybdenum/copper (Mo/Cu) heterometallic cluster, [S2MoVIS2CuIS2MoVIS2]3-, noncovalently bound. The apo-ORP is able to promote the formation and stabilization of this cluster, using CuII- and MoVIS42- salts as starting metallic reagents, to yield a Mo/Cu-ORP that is virtually identical to the native ORP. In this work, we explored the ORP capability of promoting protein-assisted synthesis to prepare novel protein derivatives harboring molybdenum heterometallic clusters containing iron, cobalt, nickel, or cadmium in place of the "central" copper (Mo/Fe-ORP, Mo/Co-ORP, Mo/Ni-ORP, or Mo/Cd-ORP). For that, the previously described protein-assisted synthesis protocol was extended to other metals and the Mo/M-ORP derivatives (M = Cu, Fe, Co, Ni, or Cd) were spectroscopically (UV-visible and electron paramagnetic resonance (EPR)) characterized. The Mo/Cu-ORP and Mo/Cd-ORP derivatives are stable under oxic conditions, while the Mo/Fe-ORP, Mo/Co-ORP, and Mo/Ni-ORP derivatives are dioxygen-sensitive and stable only under anoxic conditions. The metal and protein quantification shows the formation of 2Mo:1M:1ORP derivatives, and the visible spectra suggest that the expected {S2MoS2MS2MoS2} complexes are formed. The Mo/Cu-ORP, Mo/Co-ORP, and Mo/Cd-ORP are EPR-silent. The Mo/Fe-ORP derivative shows an EPR S = 3/2 signal (E/D approximately 0.27, g approximately 5.3, 2.5, and 1.7 for the lower M= +/-1/2 doublet, and g approximately 5.7 and 1.7 (1.3 predicted) for the upper M = +/-3/2 doublet), consistent with the presence of either one S = 5/2 FeIII antiferromagnetically coupled to two S = 1/2 MoV or one S = 3/2 FeI and two S = 0 MoVI ions, in both cases in a tetrahedral geometry. The Mo/Ni-ORP shows an EPR axial S = 1/2 signal consistent with either one S = 1/2 NiI and two S = 0 MoVI or one S = 1/2 NiIII antiferromagnetically coupled to two S = 1/2 MoV ions, in both cases in a square-planar geometry. The Mo/Cu-ORP and Mo/Cd-ORP are described as {MoVI-CuI-MoVI} and {MoVI-CdII-MoVI}, respectively, while the other derivatives are suggested to exist in at least two possible electronic structures, {MoVI-MI-MoVI} \<--\> {MoV-MIII-MoV}.

}, isbn = {1520-510X (Electronic)0020-1669 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/28128558}, author = {Maiti, B. K. and Maia, L. B. and Pauleta, S. R. and Moura, I and Moura, J J} } @article {13514, title = {Biochemical characterization of the bacterial peroxidase from the human pathogen Neisseria gonorrhoeae}, journal = {Journal of Inorganic Biochemistry}, volume = {171}, year = {2017}, note = {

Cited By :4Export Date: 26 November 2019

}, month = {2017}, pages = {108 - 119}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85016820470\&doi=10.1016\%2fj.jinorgbio.2017.03.007\&partnerID=40\&md5=3c241801a34076cf2819d440bfe26214}, author = {N{\'o}brega, C. S. and Raposo, M. and Van Driessche, G. and Devreese, B and Pauleta, S. R.} } @article {13512, title = {The catalytic cycle of nitrous oxide reductase {\textemdash} The enzyme that catalyzes the last step of denitrification}, journal = {Journal of Inorganic Biochemistry}, volume = {177}, year = {2017}, note = {

Cited By :9Export Date: 26 November 2019

}, month = {2017}, pages = {423 - 434}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85029538982\&doi=10.1016\%2fj.jinorgbio.2017.09.007\&partnerID=40\&md5=052d8f06f627a23bcd874fea86cd5536}, author = {Carreira, C. and Pauleta, S. R. and Moura, I} } @article {13513, title = {Insights into the recognition and electron transfer steps in nitric oxide reductase from Marinobacter hydrocarbonoclasticus}, journal = {Journal of Inorganic Biochemistry}, volume = {177}, year = {2017}, note = {

Cited By :6Export Date: 26 November 2019

}, month = {2017}, pages = {402 - 411}, abstract = {n/a}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85029632658\&doi=10.1016\%2fj.jinorgbio.2017.09.001\&partnerID=40\&md5=9a4eded9a520a6b86683c937bb0f1889}, author = {Ramos, S. and Almeida, R. M. and Cordas, C. M. and Moura, JJG and Pauleta, S. R. and Moura, I} } @article {10968, title = {Spectroscopic Definition of the CuZ0 Intermediate in Turnover of Nitrous Oxide Reductase and Molecular Insight into the Catalytic Mechanism}, journal = {JACS}, year = {2017}, author = {E. Johnston, C. Carreira, S. Dell{\textquoteright}Acqua, S. Dey, Sofia R. Pauleta, I. Moura, E. Solomon} } @booklet {10128, title = {CHAPTER 11: Electron Transfer and Molecular Recognition in Denitrification and Nitrate Dissimilatory Pathways}, journal = {RSC Metallobiology}, volume = {2017-January}, year = {2017}, note = {

Export Date: 31 January 2017

}, pages = {252-286}, publisher = {Royal Society of Chemistry}, type = {Book Chapter}, abstract = {

The electron transfer pathways for the enzymes involved in the four sequential steps of the denitrification pathway are reviewed. In addition, brief information on the electron transfer events is also provided on two enzymes that participate in the dissimilatory nitrate reduction to ammonia. The two main aspects discussed are the intra- and inter-molecular electron transfer pathways and the molecular recognition processes involving the redox partners. When available, information on the residues that are involved in these pathways is given, and their role in electron transfer and/or the formation of the transient electron transfer complexes is discussed. {\textcopyright} The Royal Society of Chemistry 2017.

}, isbn = {2045547X (ISSN)}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85006274982\&doi=10.1039\%2f9781782623762-00252\&partnerID=40\&md5=304ac9ef4a603f183379613e48c8d124}, author = {Almeida, R. M. and Dell{\textquoteright}acqua, S. and Moura, I and Pauleta, S. R. and Moura, JJG}, editor = {Moura, I and Moura, JJG and Maia, L. B. and Garner, C. D. and Pauleta, S. R.} } @booklet {10129, title = {CHAPTER 1: A Bird{\textquoteright}s Eye View of Denitrification in Relation to the Nitrogen Cycle}, journal = {RSC Metallobiology}, volume = {2017-January}, year = {2017}, note = {

Export Date: 31 January 2017

}, pages = {1-10}, publisher = {Royal Society of Chemistry}, type = {Book Chapter}, abstract = {

This book is devoted to denitrification, an anaerobic process that is used by a wide range of bacteria for energy generation. The overall process involves nitrate, which is present in soil or water, being reduced to gaseous dinitrogen. This initial chapter aims to place denitrification in the larger context of the nitrogen biogeochemical cycle (a bird{\textquoteright}s eye view). Detailed topics are developed through the many following contributions. Denitrification is a landscape for probing the structures, functions and mechanisms of action of a wide range of highly specialised metalloenzymes. These carry out, sequentially, four oxo-transfer reactions: NO3 - {\textrightarrow} NO2 - {\textrightarrow} NO {\textrightarrow} N2O {\textrightarrow} N2. The environmental implications of these processes are of particular relevance. Nitrate accumulation and the release of nitrous oxide into the atmosphere due to the excessive use of fertilisers in agriculture are examples of two environmental problems in which denitrification plays a central role. {\textcopyright} The Royal Society of Chemistry 2017.

}, isbn = {2045547X (ISSN)}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85006272168\&doi=10.1039\%2f9781782623762-00001\&partnerID=40\&md5=f6f137ac3e3083cf9bf52845da0f959a}, author = {Moura, I and Maia, L. B. and Pauleta, S. R. and Moura, JJG}, editor = {Moura, I and Moura, JJG and Maia, L. B. and Garner, C. D. and Pauleta, S. R.} } @booklet {10130, title = {CHAPTER 7: Insights into Nitrous Oxide Reductase}, journal = {RSC Metallobiology}, volume = {2017-January}, year = {2017}, note = {

Export Date: 31 January 2017

}, pages = {141-169}, publisher = {Royal Society of Chemistry}, type = {Book Chapter}, abstract = {

Nitrous oxide reductase is the enzyme that catalyses the last step of the denitrification pathway, reducing nitrous oxide to dinitrogen gas. This enzyme is a functional homodimer with two copper centres, CuA and a "CuZ centre", located in different domains. The CuA centre is the electron transferring centre, while the catalytic centre is the "CuZ centre", a unique metal centre in biology - a tetranuclear copper centre with a μ4-bridging sulphide. The enzyme has been isolated with the "CuZ centre" in two different forms, CuZ(4Cu2S) and CuZ*(4Cu1S), with the first presenting an additional μ2-sulphur atom as a bridging ligand between CuI and CuIV of the "CuZ centre", whereas the second form was identified as a water-derived molecule. Spectroscopic analysis of CuZ*(4Cu1S), together with computational studies, indicated that there is a hydroxide bound to CuI. Genomic analysis has identified the presence of two different types of nitrous oxide reductase, the typical and "atypical", with a single member of the last group having been isolated to date, from Wolinella succinogenes. Thus, here the structure of the "typical" nitrous oxide reductase with either CuZ(4Cu2S) or CuZ*(4Cu1S), as well as its spectroscopic and catalytic properties, will be discussed. {\textcopyright} The Royal Society of Chemistry 2017.

}, isbn = {2045547X (ISSN)}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85006272405\&doi=10.1039\%2f9781782623762-00141\&partnerID=40\&md5=4f11e02bd7a4da983b55330ab3e0e33c}, author = {Pauleta, S. R. and Carreira, C. and Moura, I}, editor = {Moura, I and Moura, JJG and Maia, L. B. and Garner, C. D. and Pauleta, S. R.} } @article {10103, title = {The small iron-sulfur protein from the ORP operon binds a [2Fe-2S] cluster}, journal = {Biochim Biophys Acta}, volume = {1857}, number = {9}, year = {2016}, note = {

Maiti, Biplab KMoura, IsabelMoura, Jose J GPauleta, Sofia RNetherlandsBiochimica et biophysica actaBiochim Biophys Acta. 2016 Sep;1857(9):1422-9. doi: 10.1016/j.bbabio.2016.05.006. Epub 2016 May 27.

}, month = {Sep}, pages = {1422-9}, edition = {2016/06/01}, abstract = {

A linear cluster formulated as [S2MoS2CuS2MoS2](3-), a unique heterometallic cluster found in biological systems, was identified in a small monomeric protein (named as Orange Protein). The gene coding for this protein is part of an operon mainly present in strict anaerobic bacteria, which is composed (in its core) by genes coding for the Orange Protein and two ATPase proposed to contain Fe-S clusters. In Desulfovibrio desulfuricans G20, there is an ORF, Dde_3197 that encodes a small protein containing several cysteine residues in its primary sequence. The heterologously produced Dde_3197 aggregates mostly in inclusion bodies and was isolated by unfolding with a chaotropic agent and refolding by dialysis. The refolded protein contained sub-stoichiometric amounts of iron atoms/protein (0.5+/-0.2), but after reconstitution with iron and sulfide, high iron load contents were detected (1.8+/-0.1 or 3.4+/-0.2) using 2- and 4-fold iron excess. The visible absorption spectral features of the iron-sulfur clusters in refolded and reconstituted Dde_3197 are similar and resemble the ones of [2Fe-2S] cluster containing proteins. The refolded and reconstituted [2Fe-2S] Dde_3197 are EPR silent, but after reduction with dithionite, a rhombic signal is observed with gmax=2.00, gmed=1.95 and gmin=1.92, consistent with a one-electron reduction of a [2Fe-2S](2+) cluster into a [2Fe-2S](1+) state, with an electron spin of S=(1/2). The data suggests that Dde_3197 can harbor one or two [2Fe-2S] clusters, one being stable and the other labile, with quite identical spectroscopic properties, but stable to oxygen.

}, isbn = {0006-3002 (Print)0006-3002 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/27240719}, author = {Maiti, B. K. and Moura, I and Moura, J J and Pauleta, S. R.} } @article {10104, title = {Orange protein from Desulfovibrio alaskensis G20: insights into the Mo-Cu cluster protein-assisted synthesis}, journal = {J Biol Inorg Chem}, volume = {21}, number = {1}, year = {2016}, note = {

Carepo, Marta S PCarreira, CintiaGrazina, RaquelZakrzewska, Malgorzata EDolla, AlainAubert, CorinnePauleta, Sofia RMoura, Jose J GMoura, IsabelResearch Support, Non-U.S. Gov{\textquoteright}tGermanyJournal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic ChemistryJ Biol Inorg Chem. 2016 Mar;21(1):53-62. doi: 10.1007/s00775-015-1323-x. Epub 2016 Jan 9.

}, month = {Mar}, pages = {53-62}, edition = {2016/01/11}, abstract = {

A novel metalloprotein containing a unique [S2MoS2CuS2MoS2](3-) cluster, designated as Orange Protein (ORP), was isolated for the first time from Desulfovibrio gigas, a sulphate reducer. The orp operon is conserved in almost all sequenced Desulfovibrio genomes and in other anaerobic bacteria, however, so far D. gigas ORP had been the only ORP characterized in the literature. In this work, the purification of another ORP isolated form Desulfovibrio alaskensis G20 is reported. The native protein is monomeric (12443.8 +/- 0.1 Da by ESI-MS) and contains also a MoCu cluster with characteristic absorption bands at 337 and 480 nm, assigned to S-Mo charge transfer bands. Desulfovibrio alaskensis G20 recombinant protein was obtained in the apo-form from E. coli. Cluster reconstitution studies and UV-visible titrations with tetrathiomolybdate of the apo-ORP incubated with Cu ions indicate that the cluster is incorporated in a protein metal-assisted synthetic mode and the protein favors the 2Mo:1Cu stoichiometry. In Desulfovibrio alaskensis G20, the orp genes are encoded by a polycistronic unit composed of six genes whereas in Desulfovibrio vulgaris Hildenborough the same genes are organized into two divergent operons, although the composition in genes is similar. The gene expression of ORP (Dde_3198) increased 6.6 +/- 0.5 times when molybdate was added to the growth medium but was not affected by Cu(II) addition, suggesting an involvement in molybdenum metabolism directly or indirectly in these anaerobic bacteria.

}, keywords = {Amino Acid Sequence, Bacterial Proteins/chemistry/*metabolism, Copper/*chemistry, Desulfovibrio/*metabolism, Molecular Sequence Data, Molybdenum/*metabolism, Sequence Homology, Amino Acid, Spectrometry, Mass, Electrospray Ionization, Spectrophotometry, Ultraviolet}, isbn = {1432-1327 (Electronic)0949-8257 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/26748795}, author = {Carepo, M. S. and Carreira, C. and Grazina, R. and Zakrzewska, M. E. and Dolla, A. and Aubert, C. and Pauleta, S. R. and Moura, J J and Moura, I} } @article {10101, title = {The solution structure of the soluble form of the lipid-modified azurin from Neisseria gonorrhoeae, the electron donor of cytochrome c peroxidase}, journal = {Biochim Biophys Acta}, volume = {1857}, number = {2}, year = {2016}, note = {

Nobrega, Claudia SSaraiva, Ivo HCarreira, CintiaDevreese, BartMatzapetakis, ManolisPauleta, Sofia RResearch Support, Non-U.S. Gov{\textquoteright}tNetherlandsBiochimica et biophysica actaBiochim Biophys Acta. 2016 Feb;1857(2):169-76. doi: 10.1016/j.bbabio.2015.11.006. Epub 2015 Nov 14.

}, month = {Feb}, pages = {169-76}, edition = {2015/11/22}, abstract = {

Neisseria gonorrhoeae colonizes the genitourinary track, and in these environments, especially in the female host, the bacteria are subjected to low levels of oxygen, and reactive oxygen and nitrosyl species. Here, the biochemical characterization of N. gonorrhoeae Laz is presented, as well as, the solution structure of its soluble domain determined by NMR. N. gonorrhoeae Laz is a type 1 copper protein of the azurin-family based on its spectroscopic properties and structure, with a redox potential of 277+/-5 mV, at pH7.0, that behaves as a monomer in solution. The globular Laz soluble domain adopts the Greek-key motif, with the copper center located at one end of the beta-barrel coordinated by Gly48, His49, Cys113, His118 and Met122, in a distorted trigonal geometry. The edge of the His118 imidazole ring is water exposed, in a surface that is proposed to be involved in the interaction with its redox partners. The heterologously expressed Laz was shown to be a competent electron donor to N. gonorrhoeae cytochrome c peroxidase. This is an evidence for its involvement in the mechanism of protection against hydrogen peroxide generated by neighboring lactobacilli in the host environment.

}, keywords = {*Electrons, Amino Acid Sequence, Azurin/*chemistry/genetics/metabolism, Cloning, Molecular, Copper/*chemistry/metabolism, Cytochrome-c Peroxidase/*chemistry/genetics/metabolism, Electron Transport, Escherichia coli/genetics/metabolism, Gene Expression, Hydrogen Peroxide/*chemistry, Models, Molecular, Molecular Sequence Data, Neisseria gonorrhoeae/*chemistry/enzymology, Oxidation-Reduction, Protein Folding, Protein Structure, Secondary, Protein Structure, Tertiary, Recombinant Proteins/chemistry/genetics/metabolism, Substrate Specificity}, isbn = {0006-3002 (Print)0006-3002 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/26589091}, author = {Nobrega, C. S. and Saraiva, I. H. and Carreira, C. and Devreese, B and Matzapetakis, M. and Pauleta, S. R.} } @article {10105, title = {Predicting Protein-Protein Interactions Using BiGGER: Case Studies}, journal = {Molecules}, volume = {21}, number = {8}, year = {2016}, note = {

Almeida, Rui MDell{\textquoteright}Acqua, SimoneKrippahl, LudwigMoura, Jose J GPauleta, Sofia RSwitzerlandMolecules (Basel, Switzerland)Molecules. 2016 Aug 9;21(8). pii: E1037. doi: 10.3390/molecules21081037.

}, month = {Aug 09}, edition = {2016/08/16}, abstract = {

The importance of understanding interactomes makes preeminent the study of protein interactions and protein complexes. Traditionally, protein interactions have been elucidated by experimental methods or, with lower impact, by simulation with protein docking algorithms. This article describes features and applications of the BiGGER docking algorithm, which stands at the interface of these two approaches. BiGGER is a user-friendly docking algorithm that was specifically designed to incorporate experimental data at different stages of the simulation, to either guide the search for correct structures or help evaluate the results, in order to combine the reliability of hard data with the convenience of simulations. Herein, the applications of BiGGER are described by illustrative applications divided in three Case Studies: (Case Study A) in which no specific contact data is available; (Case Study B) when different experimental data (e.g., site-directed mutagenesis, properties of the complex, NMR chemical shift perturbation mapping, electron tunneling) on one of the partners is available; and (Case Study C) when experimental data are available for both interacting surfaces, which are used during the search and/or evaluation stage of the docking. This algorithm has been extensively used, evidencing its usefulness in a wide range of different biological research fields.

}, isbn = {1420-3049 (Electronic)1420-3049 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/27517887}, author = {Almeida, R. M. and Dell{\textquoteright}acqua, S. and Krippahl, L. and Moura, J J and Pauleta, S. R.} } @article {10102, title = {Resonance assignment of DVU2108 that is part of the Orange Protein complex in Desulfovibrio vulgaris Hildenborough}, journal = {Biomol NMR Assign}, volume = {10}, number = {1}, year = {2016}, note = {

Neca, Antonio JSoares, RuiCarepo, Marta S PPauleta, Sofia RResearch Support, Non-U.S. Gov{\textquoteright}tNetherlandsBiomolecular NMR assignmentsBiomol NMR Assign. 2016 Apr;10(1):117-20. doi: 10.1007/s12104-015-9648-5. Epub 2015 Sep 15.

}, month = {Apr}, pages = {117-20}, edition = {2015/09/17}, abstract = {

We report the 94 \% assignment of DVU2108, a protein belonging to the Orange Protein family, that in Desulfovibrio vulgaris Hildenborough forms a protein complex named the Orange Protein complex. This complex has been shown to be implicated in the cell division of this organism. DVU2108 is a conserved protein in anaerobic microorganisms and in Desulfovibrio gigas the homologous protein was isolated with a novel Mo-Cu cluster non-covalently attached to the polypeptide chain. However, the heterologously produced DVU2108 did not contain any bound metal. These assignments provide the means to characterize the interaction of DVU2108 with the proteins that form the Orange Protein complex using NMR methods.

}, keywords = {*Desulfovibrio vulgaris, *Nuclear Magnetic Resonance, Biomolecular, Amino Acid Sequence, Bacterial Proteins/*chemistry/*metabolism}, isbn = {1874-270X (Electronic)1874-270X (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/26373427}, author = {Neca, A. J. and R. Soares and Carepo, M. S. and Pauleta, S. R.} } @article {10107, title = {Protonation state of the Cu4S2 CuZ site in nitrous oxide reductase: redox dependence and insight into reactivity}, journal = {Chem Sci}, volume = {6}, number = {10}, year = {2015}, note = {

Johnston, Esther MDell{\textquoteright}Acqua, SimonePauleta, Sofia RMoura, IsabelSolomon, Edward IR01 DK031450/DK/NIDDK NIH HHS/United StatesEnglandChemical scienceChem Sci. 2015 Oct 1;6(10):5670-5679. Epub 2015 Jul 3.

}, month = {Oct 01}, pages = {5670-5679}, edition = {2015/09/30}, abstract = {

Spectroscopic and computational methods have been used to determine the protonation state of the edge sulfur ligand in the Cu4S2 CuZ form of the active site of nitrous oxide reductase (N2OR) in its 3CuICuII (1-hole) and 2CuI2CuII (2-hole) redox states. The EPR, absorption, and MCD spectra of 1-hole CuZ indicate that the unpaired spin in this site is evenly delocalized over CuI, CuII, and CuIV. 1-hole CuZ is shown to have a mu2-thiolate edge ligand from the observation of S-H bending modes in the resonance Raman spectrum at 450 and 492 cm-1 that have significant deuterium isotope shifts (-137 cm-1) and are not perturbed up to pH 10. 2-hole CuZ is characterized with absorption and resonance Raman spectroscopies as having two Cu-S stretching vibrations that profile differently. DFT models of the 1-hole and 2-hole CuZ sites are correlated to these spectroscopic features to determine that 2-hole CuZ has a mu2-sulfide edge ligand at neutral pH. The slow two electron (+1 proton) reduction of N2O by 1-hole CuZ is discussed and the possibility of a reaction between 2-hole CuZ and O2 is considered.

}, isbn = {2041-6520 (Print)2041-6520 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/26417423}, author = {Johnston, E. M. and Dell{\textquoteright}acqua, S. and Pauleta, S. R. and Moura, I and Solomon, E. I.} } @article {10106, title = {Incorporation of molybdenum in rubredoxin: models for mononuclear molybdenum enzymes}, journal = {J Biol Inorg Chem}, volume = {20}, number = {5}, year = {2015}, note = {

Maiti, Biplab KMaia, Luisa BSilveira, Celia MTodorovic, SmiljaCarreira, CintiaCarepo, Marta S PGrazina, RaquelMoura, IsabelPauleta, Sofia RMoura, Jose J GResearch Support, Non-U.S. Gov{\textquoteright}tGermanyJournal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic ChemistryJ Biol Inorg Chem. 2015 Jul;20(5):821-9. doi: 10.1007/s00775-015-1268-0. Epub 2015 May 7.

}, month = {Jul}, pages = {821-9}, edition = {2015/05/08}, abstract = {

Molybdenum is found in the active site of enzymes usually coordinated by one or two pyranopterin molecules. Here, we mimic an enzyme with a mononuclear molybdenum-bis pyranopterin center by incorporating molybdenum in rubredoxin. In the molybdenum-substituted rubredoxin, the metal ion is coordinated by four sulfurs from conserved cysteine residues of the apo-rubredoxin and two other exogenous ligands, oxygen and thiol, forming a Mo((VI))-(S-Cys)4(O)(X) complex, where X represents -OH or -SR. The rubredoxin molybdenum center is stabilized in a Mo(VI) oxidation state, but can be reduced to Mo(IV) via Mo(V) by dithionite, being a suitable model for the spectroscopic properties of resting and reduced forms of molybdenum-bis pyranopterin-containing enzymes. Preliminary experiments indicate that the molybdenum site built in rubredoxin can promote oxo transfer reactions, as exemplified with the oxidation of arsenite to arsenate.

}, keywords = {Electrochemical Techniques, Electron Spin Resonance Spectroscopy, Molecular Structure, Molybdenum/chemistry/*metabolism, Oxidoreductases/chemistry/*metabolism, Rubredoxins/chemistry/*metabolism}, isbn = {1432-1327 (Electronic)0949-8257 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/25948393}, author = {Maiti, B. K. and Maia, L. B. and Silveira, C. M. and Todorovic, S. and Carreira, C. and Carepo, M. S. and Grazina, R. and Moura, I and Pauleta, S. R. and Moura, J J} } @conference {10127, title = {HCN Channels: The Molecular Basis for their cAMP-TRIP8b Regulation}, booktitle = {Biophysical Journal}, volume = {108}, number = {2}, year = {2015}, note = {

Suppl. 1Ct5ku1839-PlatTimes Cited:0Cited References Count:4

}, month = {Jan 27}, pages = {366a-366a}, abstract = {n/a}, keywords = {camp}, isbn = {0006-3495}, url = {://000362849400254}, author = {Saponaro, A. and Donadoni, C. and Pauleta, S. R. and Cantini, F. and Matzapetakis, M. and Thiel, G. and Banci, L. and Santoro, B. and Moroni, A.} } @article {10108, title = {Structural basis for the mutual antagonism of cAMP and TRIP8b in regulating HCN channel function}, journal = {Proc Natl Acad Sci U S A}, volume = {111}, number = {40}, year = {2014}, note = {

Saponaro, AndreaPauleta, Sofia RCantini, FrancescaMatzapetakis, ManolisHammann, ChristianDonadoni, ChiaraHu, LeiThiel, GerhardBanci, LuciaSantoro, BinaMoroni, AnnaR01 NS036658/NS/NINDS NIH HHS/United StatesR56 NS036658/NS/NINDS NIH HHS/United StatesNS36658/NS/NINDS NIH HHS/United StatesResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov{\textquoteright}tUnited StatesProceedings of the National Academy of Sciences of the United States of AmericaProc Natl Acad Sci U S A. 2014 Oct 7;111(40):14577-82. doi: 10.1073/pnas.1410389111. Epub 2014 Sep 2.

}, month = {Oct 07}, pages = {14577-82}, edition = {2014/09/10}, abstract = {

cAMP signaling in the brain mediates several higher order neural processes. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels directly bind cAMP through their cytoplasmic cyclic nucleotide binding domain (CNBD), thus playing a unique role in brain function. Neuronal HCN channels are also regulated by tetratricopeptide repeat-containing Rab8b interacting protein (TRIP8b), an auxiliary subunit that antagonizes the effects of cAMP by interacting with the channel CNBD. To unravel the molecular mechanisms underlying the dual regulation of HCN channel activity by cAMP/TRIP8b, we determined the NMR solution structure of the HCN2 channel CNBD in the cAMP-free form and mapped on it the TRIP8b interaction site. We reconstruct here the full conformational changes induced by cAMP binding to the HCN channel CNBD. Our results show that TRIP8b does not compete with cAMP for the same binding region; rather, it exerts its inhibitory action through an allosteric mechanism, preventing the cAMP-induced conformational changes in the HCN channel CNBD.

}, keywords = {*Ion Channel Gating, Binding Sites, Channels/*chemistry/metabolism, Crystallography, X-Ray, Cyclic AMP/*chemistry/metabolism, Cyclic Nucleotide-Gated Cation Channels/chemistry/metabolism, Electrophoresis, Polyacrylamide Gel, Humans, Hyperpolarization-Activated Cyclic Nucleotide-Gated, Magnetic Resonance Spectroscopy, Models, Molecular, Molecular Structure, Potassium Channels/chemistry/metabolism, Protein Binding, Protein Structure, Secondary, Protein Structure, Tertiary, Receptors, Cytoplasmic and Nuclear/*chemistry/metabolism}, isbn = {1091-6490 (Electronic)0027-8424 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/25197093}, author = {Saponaro, A. and Pauleta, S. R. and Cantini, F. and Matzapetakis, M. and Hammann, C. and Donadoni, C. and Hu, L. and Thiel, G. and Banci, L. and Santoro, B. and Moroni, A.} } @conference {10125, title = {INSIGHTS INTO THE CATALYTICCYCLE OF Pseudomonas nautica NITROUS OXIDE REDUCTASE}, booktitle = {Journal of Biological Inorganic Chemistry}, volume = {19}, year = {2014}, note = {

Suppl. 1Ac9du1711116Times Cited:0Cited References Count:5

}, month = {Mar}, pages = {S104-S104}, abstract = {n/a}, isbn = {0949-8257}, url = {://000332835300051}, author = {Moura, I and Carreira, C. and Pauleta, S. and Nunes, R. F. and Moura, J J and Ramos, S. and Dell{\textquoteright}acqua, S. and Einsle, O.} } @article {10112, title = {Mo-Cu metal cluster formation and binding in an orange protein isolated from Desulfovibrio gigas}, journal = {J Biol Inorg Chem}, volume = {19}, number = {4-5}, year = {2014}, note = {

Carepo, Marta S PPauleta, Sofia RWedd, Anthony GMoura, Jose J GMoura, IsabelResearch Support, Non-U.S. Gov{\textquoteright}tGermanyJournal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic ChemistryJ Biol Inorg Chem. 2014 Jun;19(4-5):605-14. doi: 10.1007/s00775-014-1107-8. Epub 2014 Jan 30.

}, month = {Jun}, pages = {605-14}, edition = {2014/01/31}, abstract = {

The orange protein (ORP) isolated from the sulfate-reducing bacterium Desulfovibrio gigas (11.8 kDa) contains a mixed-metal sulfide cluster of the type [S2MoS2CuS2MoS2](3-) noncovalently bound to the polypeptide chain. The D. gigas ORP was heterologously produced in Escherichia coli in the apo form. Different strategies were used to reconstitute the metal cluster into apo-ORP and obtain insights into the metal cluster synthesis: (1) incorporation of a synthesized inorganic analogue of the native metal cluster and (2) the in situ synthesis of the metal cluster on the addition to apo-ORP of copper chloride and tetrathiomolybdate or tetrathiotungstate. This latter procedure was successful, and the visible spectrum of the Mo-Cu reconstituted ORP is identical to the one reported for the native protein with absorption maxima at 340 and 480 nm. The (1)H-(15)N heteronuclear single quantum coherence spectra of the reconstituted ORP obtained by strategy 2, in contrast to strategy 1, exhibited large changes, which required sequential assignment in order to identify, by chemical shift differences, the residues affected by the incorporation of the cluster, which is stabilized inside the protein by both electrostatic and hydrophobic interactions.

}, keywords = {Bacterial Proteins/chemistry/*metabolism, Copper/chemistry/*metabolism, Desulfovibrio gigas/chemistry/*metabolism, Molybdenum/chemistry/*metabolism}, isbn = {1432-1327 (Electronic)0949-8257 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/24477945}, author = {Carepo, M. S. and Pauleta, S. R. and Wedd, A. G. and Moura, J J and Moura, I} } @article {10110, title = {Synthesis and characterization of [S2MoS2Cu(n-SPhF)](2-) (n = o, m, P) clusters: Potential F-19-NMR structural probes for Orange Protein}, journal = {Inorganic Chemistry Communications}, volume = {45}, year = {2014}, note = {

Ak7mrTimes Cited:2Cited References Count:28

}, month = {Jul}, pages = {97-100}, abstract = {

Three fluorinated Mo-Cu-thiolate isomers,[Ph4Ph[S2MoS2Cu(n-SPhF)], [n-SPhF = 2-fluorothiophenol (la)], 3-fluorothiophenol (lb), and 4-fluorothiophenol (1c)] were synthesized and spectroscopically characterized. The F-19-NMR signal of the fluorine atom in the.benzene has different chemical shift for each isomer, which is highly influenced by the local environment that can be manipulated by different solvents and solutes. The fluorine-19 chemical shift is an advantageous NMR structural probe in alternative to H-1-NMR [B.K. Maiti, T. Aviles, M. Matzapetakis, I. Moura, S.R. Pauleta, JJ.G. Moura, Eur. J. Inorg. Chem. (2012) 4159.], that can be used to provide local information on the pocket of the metal cluster in the Orange Protein (ORP). (C) 2014 Elsevier B.V. All rights reserved.

}, keywords = {complexes, conformation, copper, f-19-nmr, local environment, mercury, metallothioneins, molybdenum, molybdenum-copper-sulfur, nmr-spectroscopy, Orange protein (ORP), relevance, structural probe}, isbn = {1387-7003}, url = {://000338612900024}, author = {Maiti, B. K. and Aviles, T. and Moura, I and Pauleta, S. R. and Moura, JJG} } @conference {10126, title = {The Auxiliary Subunit TRIP8B Inhibits the Binding of CAMP to HCN2 Channels Through an Allosteric Mechanism}, booktitle = {Biophysical Journal}, volume = {106}, number = {2}, year = {2014}, note = {

Suppl. 1Ai6qeTimes Cited:0Cited References Count:3

}, month = {Jan 28}, pages = {758a-758a}, abstract = {n/a}, isbn = {0006-3495}, url = {://000337000404288}, author = {Saponaro, A. C. and Matzapetakis, M. and Santoro, B. and Pauleta, S. R. and Moroni, A.} } @article {10111, title = {Determination of the active form of the tetranuclear copper sulfur cluster in nitrous oxide reductase}, journal = {J Am Chem Soc}, volume = {136}, number = {2}, year = {2014}, note = {

Johnston, Esther MDell{\textquoteright}Acqua, SimoneRamos, SusanaPauleta, Sofia RMoura, IsabelSolomon, Edward IR01 DK031450/DK/NIDDK NIH HHS/United StatesR37 DK031450/DK/NIDDK NIH HHS/United StatesDK-31450/DK/NIDDK NIH HHS/United StatesResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov{\textquoteright}tUnited StatesJournal of the American Chemical SocietyJ Am Chem Soc. 2014 Jan 15;136(2):614-7. doi: 10.1021/ja411500p. Epub 2014 Jan 7.

}, month = {Jan 15}, pages = {614-7}, edition = {2013/12/25}, abstract = {

N2OR has been found to have two structural forms of its tetranuclear copper active site, the 4CuS Cu(Z)* form and the 4Cu2S Cu(Z) form. EPR, resonance Raman, and MCD spectroscopies have been used to determine the redox states of these sites under different reductant conditions, showing that the Cu(Z)* site accesses the 1-hole and fully reduced redox states, while the Cu(Z) site accesses the 2-hole and 1-hole redox states. Single-turnover reactions of N2OR for Cu(Z) and Cu(Z)* poised in these redox states and steady-state turnover assays with different proportions of Cu(Z) and Cu(Z)* show that only fully reduced Cu(Z)* is catalytically competent in rapid turnover with N2O.

}, keywords = {Copper/chemistry/*metabolism, Marinobacter/*enzymology, Models, Molecular, Oxidoreductases/chemistry/*metabolism, Sulfur/chemistry/*metabolism}, isbn = {1520-5126 (Electronic)0002-7863 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/24364717}, author = {Johnston, E. M. and Dell{\textquoteright}acqua, S. and Ramos, S. and Pauleta, S. R. and Moura, I and Solomon, E. I.} } @article {10109, title = {One electron reduced square planar bis(benzene-1,2-dithiolato) copper dianionic complex and redox switch by O2/HO(-)}, journal = {Inorg Chem}, volume = {53}, number = {24}, year = {2014}, note = {

Maiti, Biplab KMaia, Luisa BPal, KuntalPakhira, BholanathAviles, TeresaMoura, IsabelPauleta, Sofia RNunez, Jose LRizzi, Alberto CBrondino, Carlos DSarkar, SabyasachiMoura, Jose J GUnited StatesInorganic chemistryInorg Chem. 2014 Dec 15;53(24):12799-808. doi: 10.1021/ic501742j. Epub 2014 Dec 3.

}, month = {Dec 15}, pages = {12799-808}, edition = {2014/12/04}, abstract = {

The complex [Ph4P]2[Cu(bdt)2] (1(red)) was synthesized by the reaction of [Ph4P]2[S2MoS2CuCl] with H2bdt (bdt = benzene-1,2-dithiolate) in basic medium. 1(red) is highly susceptible toward dioxygen, affording the one electron oxidized diamagnetic compound [Ph4P][Cu(bdt)2] (1(ox)). The interconversion between these two oxidation states can be switched by addition of O2 or base (Et4NOH = tetraethylammonium hydroxide), as demonstrated by cyclic voltammetry and UV-visible and EPR spectroscopies. Thiomolybdates, in free or complex forms with copper ions, play an important role in the stability of 1(red) during its synthesis, since in its absence, 1(ox) is isolated. Both 1(red) and 1(ox) were structurally characterized by X-ray crystallography. EPR experiments showed that 1(red) is a Cu(II)-sulfur complex and revealed strong covalency on the copper-sulfur bonds. DFT calculations confirmed the spin density delocalization over the four sulfur atoms (76\%) and copper (24\%) atom, suggesting that 1(red) has a "thiyl radical character". Time dependent DFT calculations identified such ligand to ligand charge transfer transitions. Accordingly, 1(red) is better described by the two isoelectronic structures [Cu(I)(bdt2, 4S(3-,)*)](2-) \<--\> [Cu(II)(bdt2, 4S(4-))](2-). On thermodynamic grounds, oxidation of 1(red) (doublet state) leads to 1(ox) singlet state, [Cu(III)(bdt2, 4S(4-))](1-).

}, isbn = {1520-510X (Electronic)0020-1669 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/25470763}, author = {Maiti, B. K. and Maia, L. B. and Pal, K. and Pakhira, B. and Aviles, T. and Moura, I and Pauleta, S. R. and Nunez, J. L. and Rizzi, A. C. and Brondino, CD and Sarkar, S. and Moura, J J} } @conference {10123, title = {Electronic structure and reactivities of resting and intermediate forms of the tetranuclear copper cluster in nitrous oxide reductase}, booktitle = {Abstracts of Papers of the American Chemical Society}, volume = {248}, year = {2014}, note = {

Ca8kc879-INORTimes Cited:0Cited References Count:4

}, month = {Aug 10}, abstract = {n/a}, keywords = {sulfur}, isbn = {0065-7727}, url = {://000349167401517}, author = {Johnston, E. M. and Dell{\textquoteright}acqua, S. and Gorelsky, S. and Pauleta, S. R. and Moura, I and Solomon, E. I.} } @conference {10124, title = {Metal substituted rubredoxins: a sulfur rich coordination site as models for metalloenzymes}, booktitle = {Journal of Biological Inorganic Chemistry}, volume = {19}, year = {2014}, note = {

Suppl. 2Am5cyIl 18Times Cited:0Cited References Count:4

}, month = {Aug}, pages = {S731-S731}, abstract = {n/a}, keywords = {forms}, isbn = {0949-8257}, url = {://000339874700069}, author = {Moura, JJG and Maiti, B. K. and Carreira, C. and Maia, L. B. and Carepo, S. P. and Pauleta, S. R. and Moura, I} } @article {10119, title = {Superoxide reductase: different interaction modes with its two redox partners}, journal = {ChemBioChem}, volume = {14}, number = {14}, year = {2013}, note = {

Almeida, Rui MTurano, PaolaMoura, IsabelMoura, Jose J GPauleta, Sofia RResearch Support, Non-U.S. Gov{\textquoteright}tGermanyChembiochem : a European journal of chemical biologyChembiochem. 2013 Sep 23;14(14):1858-66. doi: 10.1002/cbic.201300196. Epub 2013 Aug 22.

}, month = {Sep 23}, pages = {1858-66}, edition = {2013/09/17}, abstract = {

Anaerobic organisms have molecular systems to detoxify reactive oxygen species when transiently exposed to oxygen. One of these systems is superoxide reductase, which reduces O2 (.-) to H2 O2 without production of molecular oxygen. In order to complete the reduction of superoxide anion, superoxide reductase requires an electron, delivered by its redox partners, which in Desulfovibrio gigas are rubredoxin and/or desulforedoxin. In this work, we characterized the interaction of Desulfovibrio gigas superoxide reductase with both electron donors by using steady-state kinetics, 2D NMR titrations, and backbone relaxation measurements. The rubredoxin surface involved in the electron transfer complex with superoxide reductase comprises the solvent-exposed hydrophobic residues in the vicinity of its metal center (Cys9, Gly10, Cys42, Gly43, and Ala44), and a Kd of 3 muM at 59 mM ionic strength was estimated by NMR. The ionic strength dependence of superoxide-mediated rubredoxin oxidation by superoxide reductase has a maximum kapp of (37 +/- 12) min(-1) at 157 mM. Relative to the electron donor desulforedoxin, its complex with superoxide reductase was not detected by chemical shift perturbation, though this protein is able to transfer electrons to superoxide reductase with a maximum kapp of (31 +/- 7) min(-1) at an ionic strength of 57 mM. Competition experiments using steady-state kinetics and NMR spectroscopy (backbone relaxation measurements and use of a paramagnetic relaxation enhancement probe) with Fe-desulforedoxin in the presence of (15) N-Zn-rubredoxin showed that these two electron donors compete for the same site on the enzyme surface, as shown in the model structure of the complex generated by using restrained molecular docking calculations. These combined strategies indicate that the two small electron donors bind in different manners, with the desulforedoxin complex being a short lived electron transfer complex or more dynamic, with many equivalent kinetically competent orientations.

}, keywords = {Desulfovibrio gigas/enzymology, Electron Transport, Hydrogen Peroxide/chemistry, Iron-Sulfur Proteins/*chemistry/metabolism, Kinetics, Molecular Docking Simulation, Nuclear Magnetic Resonance, Biomolecular, Osmolar Concentration, Oxidation-Reduction, Oxidoreductases/*chemistry/genetics/metabolism, Recombinant Proteins/biosynthesis/chemistry/genetics, Rubredoxins/*chemistry/metabolism, Superoxides/chemistry}, isbn = {1439-7633 (Electronic)1439-4227 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/24038730}, author = {Almeida, R. M. and Turano, P. and Moura, I and Moura, J J and Pauleta, S. R.} } @article {10115, title = {(1)H, (13)C and (15)N resonance assignment of the soluble form of the Lipid-modified Azurin from Neisseria gonorrhoeae}, journal = {Biomol NMR Assign}, volume = {7}, number = {2}, year = {2013}, note = {n/a}, month = {Oct}, pages = {311-4}, abstract = {

Lipid-modified azurin (Laz) from Neisseria gonorrhoeae is a type 1 copper protein proposed to be the electron donor to several enzymes involved in the resistance mechanism to reactive oxygen and nitrogen species. Here we report the backbone and side-chain resonance assignment of Laz in the reduced form, which has been complete at 97~\%. The predicted secondary structure indicates that this protein belongs to the azurin subfamily of type 1 copper proteins.

}, isbn = {1874-270X}, url = {http://www.ncbi.nlm.nih.gov/pubmed/23070845}, author = {N{\'o}brega, C. S. and Matzapetakis, M. and Pauleta, S. R.} } @article {10113, title = {Copper-substituted forms of the wild type and C42A variant of rubredoxin}, journal = {J Inorg Biochem}, volume = {127}, year = {2013}, note = {

Thapper, AndersRizzi, Alberto CBrondino, Carlos DWedd, Anthony GPais, Ricardo JMaiti, Biplab KMoura, IsabelPauleta, Sofia RMoura, Jose J GResearch Support, Non-U.S. Gov{\textquoteright}tUnited StatesJournal of inorganic biochemistryJ Inorg Biochem. 2013 Oct;127:232-7. doi: 10.1016/j.jinorgbio.2013.06.003. Epub 2013 Jun 13.

}, month = {Oct}, pages = {232-7}, edition = {2013/07/09}, abstract = {

In order to gain insights into the interplay between Cu(I) and Cu(II) in sulfur-rich protein environments, the first preparation and characterization of copper-substituted forms of the wild-type rubredoxin (Rd) from Desulfovibrio vulgaris Hildenborough are reported, as well as those of its variant C42A-Rd. The initial products appear to be tetrahedral Cu(I)(S-Cys)n species for the wild type (n=4) and the variant C42A (n=3, with an additional unidentified ligand). These species are unstable to aerial oxidation to products, whose properties are consistent with square planar Cu(II)(S-Cys)n species. These Cu(II) intermediates are susceptible to auto-reduction by ligand S-Cys to produce stable Cu(I) final products. The original Cu(I) center in the wild-type system can be regenerated by reduction, suggesting that the active site can accommodate Cu(I)(S-Cys)2 and Cys-S-S-Cys fragments in the final product. The absence of one S-Cys ligand prevents similar regeneration in the C42A-Rd system. These results emphasize the redox instability of Cu(II)-(S-Cys)n centers.

}, keywords = {Copper/*chemistry, Genetic Variation, Molecular Structure, Rubredoxins/*chemistry/genetics}, isbn = {1873-3344 (Electronic)0162-0134 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/23829948}, author = {Thapper, A. and Rizzi, A. C. and Brondino, CD and Wedd, A. G. and Pais, R. J. and Maiti, B. K. and Moura, I and Pauleta, S. R. and Moura, J J} } @conference {10121, title = {Physiological and Biochemical insights into the E. coli cytochrome c peroxidase}, booktitle = {European Biophysics Journal with Biophysics Letters}, volume = {42}, year = {2013}, note = {

Suppl. 1296WETimes Cited:0Cited References Count:0

}, month = {Jul}, pages = {S179-S179}, abstract = {n/a}, isbn = {0175-7571}, url = {://000330215300551}, author = {Nobrega, C. S. and Pauleta, S. R.} } @conference {10120, title = {Structural rearrangements occurring on HCN2 CNBD domain upon cAMP binding}, booktitle = {European Biophysics Journal with Biophysics Letters}, volume = {42}, year = {2013}, note = {

Suppl. 1296WETimes Cited:0Cited References Count:2

}, month = {Jul}, pages = {S181-S181}, abstract = {n/a}, isbn = {0175-7571}, url = {://000330215300559}, author = {Saponaro, A. and Matzapetakis, M. and Moroni, A. and Pauleta, S.} } @article {10114, title = {Nitrous oxide reductase}, journal = {Coordination Chemistry Reviews}, volume = {257}, number = {2}, year = {2013}, note = {

Times Cited: 0 Pauleta, Sofia R. Dell{\textquoteright}Acqua, Simone Moura, Isabel SI

}, month = {Jan}, pages = {332-349}, abstract = {

Nitrous oxide is a potent greenhouse gas, whose atmospheric concentration has been increasing since the introduction of the Haber Bosch process led to the widespread use of nitrogenous fertilizers. One of the pathways to its destruction is reduction to molecular nitrogen by the enzyme nitrous oxide reductase found in denitrifying bacteria. This enzyme catalyzes the last step of the denitrification pathway. It has two copper centers, a binuclear CuA center, similar to the one found in cytochrome c oxidase, and the CuZ center, a unique tetranuclear copper center now known to possess either one or two sulfide bridges. Nitrous oxide reductase has been isolated in different forms, depending on the oxidation state and molecular forms of its Cu centers. Recently, the structure of a purple form, which has both centers in the oxidized state, revealed that the CuZ center has the form [Cu4S2]. This review summarizes the biogenesis and regulation of nitrous oxide reductase, and the spectroscopic and kinetic properties of nitrous oxide reductase. The proposed activation and catalytic mechanism, as well as, electron transfer pathways are discussed in the light of the various structures of the CuZ center. (C) 2012 Published by Elsevier B.V.

}, isbn = {0010-8545}, url = {://WOS:000312762200003}, author = {Pauleta, S. R. and Dell{\textquoteright}acqua, S. and Moura, I} } @inbook {10117, title = {Iron-sulfur centers: new roles for ancient metal sites}, booktitle = {Comprehensive Inorganic Chemistry II}, volume = {3}, number = {Bioinorganic Fundamentals and Applications: Metals in Natural Living Systems and Metals in Toxicology and Medicine}, year = {2013}, note = {n/a}, pages = {103-148}, publisher = {Elsevier}, organization = {Elsevier}, chapter = {3.06}, abstract = {n/a}, isbn = {9780080977744}, author = {Grazina, R. and Pauleta, S. R. and Moura, JJG and Moura, I}, editor = {Pecoraro, V. and Hambley, T.} } @conference {10122, title = {Marinobacter hydrocarbonoclasticus is an aerobic denitrifier}, booktitle = {11th European Biological Inorganic Chemistry Conference (Eurobic 11)}, year = {2013}, note = {

Bhh40Times Cited:0Cited References Count:17

}, pages = {49-52}, abstract = {

Marinobacter hydrocarbonoclasticus is a marine bacterium widespread in the Mediterranean sea and Atlantic Ocean, and growing at temperate temperatures. This bacterium can perform complete denitrification, reducing nitrate to molecular nitrogen under anaerobic conditions. Here the nitrite concentration, pH and nitrous oxide reductase activity was monitored during bacterial growth, showing that this bacterium can also perform complete denitrification under low oxygen tension, using lactate as carbon source, in the presence of nitrate as alternative electron acceptor. Nitrous oxide reductase activity was observed after 7 h of growth under low oxygen tensions, and is maintained constant after 48h. Nitrite concentration reaches its maximum at mid-exponential phase and in the stationary phase, at lower oxygen tensions is almost non-existent.

}, keywords = {bacteria, biology, cluster, n2o, nitrous-oxide-reductase, paracoccus, pseudomonas-stutzeri, sulfur}, url = {://000325424100010}, author = {Pauleta, S. R. and Ramos, S. and Pietsch, M. and Carreira, C. and Dell{\textquoteright}acqua, S. and Moura, I} } @inbook {10118, title = {Nitrous oxide reductase}, booktitle = {Encyclopedia of Metalloproteins}, year = {2013}, note = {n/a}, publisher = {Springer}, organization = {Springer}, abstract = {n/a}, isbn = {978-1-4614-1532-9}, author = {Dell{\textquoteright}acqua, S. and Pauleta, S. R. and Moura, I and Moura, JJG}, editor = {Kretsinger, R. H. and Uversky, V. N. and Permyakov, E.A.} } @article {4548, title = {Rearrangement of Mo-Cu-S Cluster Reflects the Structural -Instability of Orange Protein Cofactor}, journal = {Zeitschrift f{\"u}r anorganische und allgemeine Chemie}, volume = {639}, number = {8-9}, year = {2013}, note = {n/a}, pages = {1361-1364}, publisher = {WILEY-VCH Verlag}, abstract = {n/a}, keywords = {Cluster rearrangement, Cubic crystal butterfly-shaped, Molybdenum/copper/sulfur cluster, Orange protein (ORP)}, isbn = {1521-3749}, url = {http://dx.doi.org/10.1002/zaac.201300034}, author = {Maiti, Biplab K. and Avil{\'e}s, Teresa and Carepo, Marta S P and Moura, Isabel and Pauleta, Sofia R and Moura, Jos{\'e} J. G.} } @article {4550, title = {Synthesis of MoS4 (2-)-M (M=Cu and Cd) Clusters: Potential NMR Spectroscopic Structural Probes for the Orange Protein}, journal = {European Journal of Inorganic Chemistry}, number = {26}, year = {2012}, note = {

Times Cited: 0 Maiti, Biplab K. Aviles, Teresa Matzapetakis, Manolis Moura, Isabel Pauleta, Sofia R. Moura, Jose J. G.

}, month = {Sep}, pages = {4159-4166}, abstract = {

Two synthetic strategies of tetrathiomolybdate-metal clusters with the potential to be used as NMR structural probes for the location of the metal cofactor in the orange protein (ORP) are described. The first strategy is based on the substitution reaction in which small organic ligands bind directly to the metal centre in a molybdenumcopper hetero-dinuclear cluster. Interaction between [PPh4]2[MoS4CuCl] and either aliphatic [beta-mercaptoethanol (b-me)] or aromatic [o-aminobenzenethiol (abt)] thiols in the presence of a strong base resulted in the formation of [Ph4P]2[S2MoS2Cu(b-me)] (1a) and [Et4N]2[S2MoS2Cu(abt)]center dot H2O center dot 0.25DMF (1b), which can be used to obtain intermolecular NOEs. The compound 1a readily hydrolyzed to [Ph4P]2[OSMoS2Cu(b-me)] (1ahydro) in contact with a protic solvent. The second strategy consisted of the incorporation of cadmium into tetrathiomolybdate ([MoS4]2), which gives rise to the trinuclear cluster compound [PPh4]2[(MoS4)2Cd] (2). All clusters were characterized spectroscopically and their structure determined by X-ray diffraction. The NMR spectroscopic data are consistent with the formation of a complex with a 1:1 ratio of {MoS4Cu} and thiol. The 113Cd NMR chemical shift of compound 2 is consistent with the cadmium having a tetrahedral geometry and coordinated by four sulfur ligands. The tetraphenylphosphonium cation in compound 1a was replaced by a tetramethylammonium countercation originating in the water-soluble compound [Me4N-1a]. Solubility in aqueous buffers is a requirement for incorporating this cluster into apo-ORP. These compounds will be used to identify the exact location of the ORP heterometallic cluster using NMR methodologies.

}, isbn = {1434-1948}, url = {://WOS:000308401600007}, author = {Maiti, B. K. and Aviles, T. and Matzapetakis, M. and Moura, I and Pauleta, S. R. and Moura, JJG} } @article {4551, title = {Analysis of resonance Raman data on the blue copper site in pseudoazurin: Excited state pi and sigma charge transfer distortions and their relation to ground state reorganization energy}, journal = {Journal of Inorganic Biochemistry}, volume = {115}, year = {2012}, note = {

Times Cited: 0 Hadt, Ryan G. Xie, Xiangjin Pauleta, Sofia R. Moura, Isabel Solomon, Edward I. SI

}, month = {Oct}, pages = {155-162}, abstract = {

The short Cu2+-S(Met) bond in pseudoazurin (PAz) results in the presence of two relatively intense S-p(pi) and S-p(sigma) charge transfer (CT) transitions. This has enabled resonance Raman (rR) data to be obtained for each excited state. The rR data show very different intensity distribution patterns for the vibrations in the 300-500 cm(-1) region. Time-dependent density functional theory (TDDFT) calculations have been used to determine that the change in intensity distribution between the S-p(pi) and S-p(sigma) excited states reflects the differential enhancement of S(Cys) backbone modes with Cu-S(Cys)-C-beta out-of-plane (oop) and in-plane (ip) bend character in their respective potential energy distributions (PEDs). The rR excited state distortions have been related to ground state reorganization energies (lambda s) and predict that, in addition to M-L stretches, the Cu-S(Cys)-C-beta oop bend needs to be considered. DFT calculations predict a large distortion in the Cu-S(Cys)-C-beta oop bending coordinate upon reduction of a blue copper (BC) site; however, this distortion is not present in the X-ray crystal structures of reduced BC sites. The lack of Cu-S(Cys)-C-beta oop distortion upon reduction corresponds to a previously unconsidered constraint on the thiolate ligand orientation in the reduced state of BC proteins and can be considered as a contribution to the entatic/rack nature of BC sites. (C) 2012 Elsevier Inc. All rights reserved.

}, isbn = {0162-0134}, url = {://WOS:000309990500021}, author = {Hadt, R. G. and Xie, X. J. and Pauleta, S. R. and Moura, I and Solomon, E. I.} } @article {1915, title = {Biochemical characterization of the purple form of Marinobacter hydrocarbonoclasticus nitrous oxide reductase}, journal = {Philos Trans R Soc Lond B Biol Sci}, volume = {367}, number = {1593}, year = {2012}, note = {

Dell{\textquoteright}Acqua, SimonePauleta, Sofia RMoura, Jose J GMoura, IsabelResearch Support, Non-U.S. Gov{\textquoteright}tEnglandPhilosophical transactions of the Royal Society of London. Series B, Biological sciencesPhilos Trans R Soc Lond B Biol Sci. 2012 May 5;367(1593):1204-12.

}, month = {May 5}, pages = {1204-12}, edition = {2012/03/28}, abstract = {

Nitrous oxide reductase (N(2)OR) catalyses the final step of the denitrification pathway-the reduction of nitrous oxide to nitrogen. The catalytic centre (CuZ) is a unique tetranuclear copper centre bridged by inorganic sulphur in a tetrahedron arrangement that can have different oxidation states. Previously, Marinobacter hydrocarbonoclasticus N(2)OR was isolated with the CuZ centre as CuZ*, in the [1Cu(2+) : 3Cu(+)] redox state, which is redox inert and requires prolonged incubation under reductive conditions to be activated. In this work, we report, for the first time, the isolation of N(2)OR from M. hydrocarbonoclasticus in the {\textquoteright}purple{\textquoteright} form, in which the CuZ centre is in the oxidized [2Cu(2+) : 2Cu(+)] redox state and is redox active. This form of the enzyme was isolated in the presence of oxygen from a microaerobic culture in the presence of nitrate and also from a strictly anaerobic culture. The purple form of the enzyme was biochemically characterized and was shown to be a redox active species, although it is still catalytically non-competent, as its specific activity is lower than that of the activated fully reduced enzyme and comparable with that of the enzyme with the CuZ centre in either the [1Cu(2+) : 3Cu(+)] redox state or in the redox inactive CuZ* state.

}, isbn = {1471-2970 (Electronic)0962-8436 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22451106}, author = {Dell{\textquoteright}acqua, S. and Pauleta, S. R. and Moura, J J and Moura, I} } @article {869, title = {Gd(III) chelates as NMR probes of protein-protein interactions. Case study: rubredoxin and cytochrome c3}, journal = {Inorg Chem}, volume = {50}, number = {21}, year = {2011}, note = {

Almeida, Rui MGeraldes, Carlos F G CPauleta, Sofia RMoura, Jose J GResearch Support, Non-U.S. Gov{\textquoteright}tUnited StatesInorganic chemistryInorg Chem. 2011 Nov 7;50(21):10600-7. Epub 2011 Sep 29.

}, month = {Nov 7}, pages = {10600-7}, edition = {2011/10/01}, abstract = {

Two cyclen-derived Gd probes, [Gd-DOTAM](3+) and [Gd-DOTP](5-) (DOTAM = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetamide; DOTP = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrakis(methylenephosphonate)), were assessed as paramagnetic relaxation enhancement (PRE)-inducing probes for characterization of protein-protein interactions. Two proteins, Desulfovibrio gigas rubredoxin and Desulfovibrio gigas cytochrome c(3), were used as model partners. In a (1)H NMR titration it was shown that [Gd-DOTP](5-) binds to cytochrome c(3) near heme IV, causing pronounced PREs, characterized by line width broadenings of the heme methyl resonances at ratios as low as 0.08. A K(d) of 23 +/- 1 muM was calculated based on chemical shift perturbation of selected heme methyl resonances belonging to three different heme groups, caused by allosteric effects upon [Gd-DOTP](5-) binding to cytochrome c(3) at a molar ratio of 2. The other probe, [Gd-DOTAM](3+), caused PREs on a well-defined patch near the metal center of rubredoxin (especially the patch constituted by residues D19-G23 and W37-S45, which broaden beyond detection). This effect was partially reversed for some resonances (C6-Y11, in particular) when cytochrome c(3) was added to this system. Both probes were successful in causing reversible PREs at the partner binding site, thus showing to be good probes to identify partners{\textquoteright} binding sites and since the interaction is reversible to structurally characterize protein complexes by better defining the complex interface.

}, isbn = {1520-510X (Electronic)0020-1669 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=PubMed\&dopt=Citation\&list_uids=21957905}, author = {Almeida, R. M. and Geraldes, C. F. and Pauleta, S. R. and Moura, J J} } @article {4554, title = {The Anaerobe-Specific Orange Protein Complex of Desulfovibrio vulgaris Hildenborough Is Encoded by Two Divergent Operons Coregulated by sigma(54) and a Cognate Transcriptional Regulator}, journal = {Journal of Bacteriology}, volume = {193}, number = {13}, year = {2011}, note = {

Times Cited: 0 Fievet, Anouchka My, Laetitia Cascales, Eric Ansaldi, Mireille Pauleta, Sofia R. Moura, Isabel Dermoun, Zorah Bernard, Christophe S. Dolla, Alain Aubert, Corinne

}, month = {Jul}, pages = {3207-3219}, abstract = {

Analysis of sequenced bacterial genomes revealed that the genomes encode more than 30\% hypothetical and conserved hypothetical proteins of unknown function. Among proteins of unknown function that are conserved in anaerobes, some might be determinants of the anaerobic way of life. This study focuses on two divergent clusters specifically found in anaerobic microorganisms and mainly composed of genes encoding conserved hypothetical proteins. We show that the two gene clusters DVU2103-DVU2104-DVU2105 (orp2) and DVU2107-DVU2108-DVU2109 (orp1) form two divergent operons transcribed by the sigma(54)-RNA polymerase. We further demonstrate that the sigma(54)-dependent transcriptional regulator DVU2106, located between orp1 and orp2, collaborates with sigma(54)-RNA polymerase to orchestrate the simultaneous expression of the divergent orp operons. DVU2106, whose structural gene is transcribed by the sigma(70)-RNA polymerase, negatively retrocontrols its own expression. By using an endogenous pulldown strategy, we identify a physiological complex composed of DVU2103, DVU2104, DVU2105, DVU2108, and DVU2109. Interestingly, inactivation of DVU2106, which is required for orp operon transcription, induces morphological defects that are likely linked to the absence of the ORP complex. A putative role of the ORP proteins in positioning the septum during cell division is discussed.

}, isbn = {0021-9193}, url = {://WOS:000291592600005}, author = {Fievet, A. and My, L. and Cascales, E. and Ansaldi, M. and Pauleta, S. R. and Moura, I and Dermoun, Z. and Bernard, C. S. and Dolla, A. and Aubert, C.} } @article {4553, title = {Artefacts induced on c-type haem proteins by electrode surfaces}, journal = {J Biol Inorg Chem}, volume = {16}, number = {2}, year = {2011}, note = {

Paes de Sousa, Patricia MPauleta, Sofia RSimoes Goncalves, M LurdesPettigrew, Graham WMoura, IsabelMoura, Jose J GCorreia dos Santos, Margarida MGermanyJournal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic ChemistryJ Biol Inorg Chem. 2011 Feb;16(2):209-15. doi: 10.1007/s00775-010-0717-z. Epub 2010 Oct 21.

}, month = {Feb}, pages = {209-15}, edition = {2010/10/22}, abstract = {

In this work it is demonstrated that the characterization of c-type haem containing proteins by electrochemical techniques needs to be cautiously performed when using pyrolytic graphite electrodes. An altered form of the cytochromes, which has a redox potential 300 mV lower than that of the native state and displays peroxidatic activity, can be induced by interaction with the pyrolytic graphite electrode. Proper control experiments need to be performed, as altered conformations of the enzymes containing c-type haems can show activity towards the enzyme substrate. The work was focused on the study of the activation mechanism and catalytic activity of cytochrome c peroxidase from Paracoccus pantotrophus. The results could only be interpreted with the assignment of the observed non-turnover and catalytic signals to a non-native conformation state of the electron-transferring haem. The same phenomenon was detected for Met-His monohaem cytochromes (mitochondrial cytochrome c and Desulfovibrio vulgaris cytochrome c-553), as well as for the bis-His multihaem cytochrome c(3) from Desulfovibrio gigas, showing that this effect is independent of the axial coordination of the c-type haem protein. Thus, the interpretation of electrochemical signals of c-type (multi)haem proteins at pyrolytic graphite electrodes must be carefully performed, to avoid misassignment of the signals and incorrect interpretation of catalytic intermediates.

}, keywords = {*Electrodes, Carbon/*chemistry, Cytochrome-c Peroxidase/chemistry, Electrochemistry/*methods, Hemeproteins/*chemistry, Paracoccus pantotrophus/enzymology, Protein Structure, Secondary}, isbn = {1432-1327 (Electronic)0949-8257 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/20963615}, author = {Paes de Sousa, P. M. and Pauleta, S. R. and Simoes Goncalves, M. L. and Pettigrew, G. W. and Moura, I and Moura, J J and Correia Dos Santos, M. M.} } @article {4555, title = {The tetranuclear copper active site of nitrous oxide reductase: the CuZ center}, journal = {Journal of Biological Inorganic Chemistry}, volume = {16}, number = {2}, year = {2011}, note = {

Times Cited: 8 Dell{\textquoteright}Acqua, Simone Pauleta, Sofia R. Moura, Isabel Moura, Jose J. G.

}, month = {Feb}, pages = {183-194}, abstract = {

This review focuses on the novel CuZ center of nitrous oxide reductase, an important enzyme owing to the environmental significance of the reaction it catalyzes, reduction of nitrous oxide, and the unusual nature of its catalytic center, named CuZ. The structure of the CuZ center, the unique tetranuclear copper center found in this enzyme, opened a novel area of research in metallobiochemistry. In the last decade, there has been progress in defining the structure of the CuZ center, characterizing the mechanism of nitrous oxide reduction, and identifying intermediates of this reaction. In addition, the determination of the structure of the CuZ center allowed a structural interpretation of the spectroscopic data, which was supported by theoretical calculations. The current knowledge of the structure, function, and spectroscopic characterization of the CuZ center is described here. We would like to stress that although many questions have been answered, the CuZ center remains a scientific challenge, with many hypotheses still being formed.

}, isbn = {0949-8257}, url = {://WOS:000286832200001}, author = {Dell{\textquoteright}acqua, S. and Pauleta, S. R. and Moura, I and Moura, JJG} } @article {874, title = {The electron transfer complex between nitrous oxide reductase and its electron donors}, journal = {J Biol Inorg Chem}, volume = {16}, number = {8}, year = {2011}, note = {

Dell{\textquoteright}acqua, SimoneMoura, IsabelMoura, Jose J GPauleta, Sofia RResearch Support, Non-U.S. Gov{\textquoteright}tGermanyJournal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic ChemistryJ Biol Inorg Chem. 2011 Dec;16(8):1241-54. doi: 10.1007/s00775-011-0812-9. Epub 2011 Jul 8.

}, month = {Dec}, pages = {1241-54}, edition = {2011/07/09}, abstract = {

Identifying redox partners and the interaction surfaces is crucial for fully understanding electron flow in a respiratory chain. In this study, we focused on the interaction of nitrous oxide reductase (N(2)OR), which catalyzes the final step in bacterial denitrification, with its physiological electron donor, either a c-type cytochrome or a type 1 copper protein. The comparison between the interaction of N(2)OR from three different microorganisms, Pseudomonas nautica, Paracoccus denitrificans, and Achromobacter cycloclastes, with their physiological electron donors was performed through the analysis of the primary sequence alignment, electrostatic surface, and molecular docking simulations, using the bimolecular complex generation with global evaluation and ranking algorithm. The docking results were analyzed taking into account the experimental data, since the interaction is suggested to have either a hydrophobic nature, in the case of P. nautica N(2)OR, or an electrostatic nature, in the case of P. denitrificans N(2)OR and A. cycloclastes N(2)OR. A set of well-conserved residues on the N(2)OR surface were identified as being part of the electron transfer pathway from the redox partner to N(2)OR (Ala495, Asp519, Val524, His566 and Leu568 numbered according to the P. nautica N(2)OR sequence). Moreover, we built a model for Wolinella succinogenes N(2)OR, an enzyme that has an additional c-type-heme-containing domain. The structures of the N(2)OR domain and the c-type-heme-containing domain were modeled and the full-length structure was obtained by molecular docking simulation of these two domains. The orientation of the c-type-heme-containing domain relative to the N(2)OR domain is similar to that found in the other electron transfer complexes.

}, isbn = {1432-1327 (Electronic)0949-8257 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=PubMed\&dopt=Citation\&list_uids=21739254}, author = {Dell{\textquoteright}acqua, S. and Moura, I and Moura, J J and Pauleta, S. R.} } @article {4559, title = {The 1.4 angstrom resolution structure of Paracoccus pantotrophus pseudoazurin}, journal = {Acta Crystallographica Section F-Structural Biology and Crystallization Communications}, volume = {66}, year = {2010}, note = {

Times Cited: 4 Najmudin, Shabir Pauleta, Sofia R. Moura, Isabel Romao, Maria J. Part 6

}, month = {Jun}, pages = {627-635}, abstract = {

Pseudoazurins are small type 1 copper proteins that are involved in the flow of electrons between various electron donors and acceptors in the bacterial periplasm, mostly under denitrifying conditions. The previously determined structure of Paracoccus pantotrophus pseudoazurin in the oxidized form was improved to a nominal resolution of 1.4 angstrom, with R and R-free values of 0.188 and 0.206, respectively. This high-resolution structure makes it possible to analyze the interactions between the monomers and the solvent structure in detail. Analysis of the high-resolution structure revealed the structural regions that are responsible for monomer-monomer recognition during dimer formation and for protein-protein interaction and that are important for partner recognition. The pseudoazurin structure was compared with other structures of various type 1 copper proteins and these were grouped into families according to similarities in their secondary structure; this may be useful in the annotation of copper proteins in newly sequenced genomes and in the identification of novel copper proteins.

}, isbn = {1744-3091}, url = {://WOS:000278165900002}, author = {Najmudin, S. and Pauleta, S. R. and Moura, I and Romao, MJ} } @article {4561, title = {Pressure Perturbation Calorimetry and the Thermodynamics of Noncovalent Interactions in Water: Comparison of Protein-Protein, Protein-Ligand, and Cyclodextrin-Adamantane Complexes}, journal = {Journal of Physical Chemistry B}, volume = {114}, number = {49}, year = {2010}, note = {

Times Cited: 7 Cameron, Diane L. Jakus, Joanna Pauleta, Sofia R. Pettigrew, Graham W. Cooper, Alan

}, month = {Dec}, pages = {16228-16235}, abstract = {

Pressure perturbation calorimetry measurements on a range of cyclodextrin adamantane, protein ligand (lysozyme-(GlcNac)(3) and ribonuclease-2{\textquoteright}CMP) and protein-protein (cytochrome c peroxidase-pseudoazurin) complexes in aqueous solution show consistent reductions in thermal expansibilities compared to the uncomplexed molecules. Thermodynamic data for binding, obtained by titration calorimetry, are also reported. Changes in molar expansibilities can be related to the decrease in solvation during complexation. Although reasonable estimates for numbers of displaced water molecules may be obtained in the case of rigid cyclodextrin-adamantane complexes, protein expansibility data are less easily reconciled. Comparison of data from this wide range of systems indicates that effects are not simply related to changes in solvent-accessible surface area, but may also involve changes in macromolecular dynamics and flexibility. This adds to the growing consensus that understanding thermodynamic parameters associated with noncovalent interactions requires consideration of changes in internal macromolecular fluctuations and dynamics that may not be related to surface area-related solvation effects alone.

}, isbn = {1520-6106}, url = {://WOS:000284990700024}, author = {Cameron, D. L. and Jakus, J. and Pauleta, S. R. and Pettigrew, G. W. and Cooper, A.} } @article {4560, title = {A new CuZ active form in the catalytic reduction of N2O by nitrous oxide reductase from Pseudomonas nautica}, journal = {Journal of Biological Inorganic Chemistry}, volume = {15}, number = {6}, year = {2010}, note = {

Times Cited: 9 Dell{\textquoteright}Acqua, Simone Pauleta, Sofia R. Paes de Sousa, Patricia M. Monzani, Enrico Casella, Luigi Moura, Jose J. G. Moura, Isabel

}, month = {Aug}, pages = {967-976}, abstract = {

The final step of bacterial denitrification, the two-electron reduction of N2O to N-2, is catalyzed by a multi-copper enzyme named nitrous oxide reductase. The catalytic centre of this enzyme is a tetranuclear copper site called CuZ, unique in biological systems. The in vitro reconstruction of the activity requires a slow activation in the presence of the artificial electron donor, reduced methyl viologen, necessary to reduce CuZ from the resting non-active state (1Cu(II)/3Cu(I)) to the fully reduced state (4Cu(I)), in contrast to the turnover cycle, which is very fast. In the present work, the direct reaction of the activated form of Pseudomonas nautica nitrous oxide reductase with stoichiometric amounts of N2O allowed the identification of a new reactive intermediate of the catalytic centre, CuZA degrees, in the turnover cycle, characterized by an intense absorption band at 680 nm. Moreover, the first mediated electrochemical study of Ps. nautica nitrous oxide reductase with its physiological electron donor, cytochrome c-552, was performed. The intermolecular electron transfer was analysed by cyclic voltammetry, under catalytic conditions, and a second-order rate constant of (5.5 +/- A 0.9) x 10(5) M-1 s(-1) was determined. Both the reaction of stoichiometric amounts of substrate and the electrochemical studies show that the active CuZA degrees species, generated in the absence of reductants, can rearrange to the resting non-active CuZ state. In this light, new aspects of the catalytic and activation/inactivation mechanism of the enzyme are discussed.

}, isbn = {0949-8257}, url = {://WOS:000280239100013}, author = {Dell{\textquoteright}acqua, S. and Pauleta, S. R. and de Sousa, P. M. P. and Monzani, E and Casella, L. and Moura, JJG and Moura, I} } @article {4566, title = {Rubredoxin as a paramagnetic relaxation-inducing probe}, journal = {Journal of Inorganic Biochemistry}, volume = {103}, number = {9}, year = {2009}, note = {

Times Cited: 4 Almeida, Rui M. Pauleta, Sofia R. Moura, Isabel Moura, Jose J. G.

}, month = {Sep}, pages = {1245-1253}, abstract = {

The paramagnetic effect due to the presence of a metal center with unpaired electrons is no longer considered a hindrance in protein NMR spectroscopy. In the present work, the paramagnetic effect due to the presence of a metal center with impaired electrons was used to map the interface of an electron transfer complex. Desulfovibrio gigas cytochrome c(3) was chosen as target to study the effect of the paramagnetic probe, Fe-rubredoxin, which produced specific line broadening in the heme IV methyl resonances M2(1) and M18(1). The rubredoxin binding surface in the complex with cytochrome c(3) was identified in a heteronuclear 2D NMR titration. The identified heme methyls on cytochrome c(3) are involved in the binding interface of the complex, a result that is in agreement with the predicted complexes obtained by restrained molecular docking, which shows a cluster of possible solutions near heme IV. The use of a paramagnetic probe in (1)HNMR titration and the mapping of the complex interface, in combination with a molecular simulation algorithm proved to be a valuable strategy to study electron transfer complexes involving non-heme iron proteins and cytochromes. (C) 2009 Elsevier Inc. All rights reserved.

}, isbn = {0162-0134}, url = {://WOS:000269962400008}, author = {Almeida, R. M. and Pauleta, S. R. and Moura, I and Moura, JJG} } @article {4563, title = {Isolation and characterization of a new Cu-Fe protein from Desulfovibrio aminophilus DSM12254}, journal = {Journal of Inorganic Biochemistry}, volume = {103}, number = {10}, year = {2009}, note = {

Times Cited: 1 Rivas, Maria G. Mota, Cristiano S. Pauleta, Sofia R. Carepo, Marta S. P. Folgosa, Filipe Andrade, Susana L. A. Fauque, Guy Pereira, Alice S. Tavares, Pedro Calvete, Juan J. Moura, Isabel Moura, Jose J. G. 1st Latin American Meeting on Biological Inorganic Chemistry (LABIC2008) AUG 31-SEP 04, 2008 Iguazu Falls, BRAZIL SI

}, month = {Oct}, pages = {1314-1322}, abstract = {

The isolation and characterization of a new metalloprotein containing Cu and Fe atoms is reported. The as-isolated Cu-Fe protein shows an UV-visible spectrum with absorption bands at 320 nm, 409 nm and 615 nm. Molecular mass of the native protein along with denaturating electrophoresis and mass spectrometry data show that this protein is a multimer consisting of 14 +/- 1 subunits of 15254.3 +/- 7.6 Da. Mossbauer spectroscopy data of the as-isolated Cu-Fe protein is consistent with the presence of [2Fe-2S](2+) centers. Data interpretation of the dithionite reduced protein suggest that the metallic cluster could be constituted by two ferromagnetically coupled [2Fe-2S](+) spin delocalized pairs. The biochemical properties of the Cu-Fe protein are similar to the recently reported molybdenum resistance associated protein from Desulfovibrio, D. alaskensis. Further-more, a BLAST search from the DNA deduced amino acid sequence shows that the Cu-Fe protein has homology with proteins annotated as zinc resistance associated proteins from Desulfovibrio, D. alaskensis, D. vulgaris Hildenborough, D. piger ATCC 29098. These facts suggest a possible role of the Cu-Fe protein in metal tolerance. (C) 2009 Published by Elsevier Inc.

}, isbn = {0162-0134}, url = {://WOS:000270795900004}, author = {Rivas, M. G. and Mota, C. S. and Pauleta, S. R. and Carepo, M. S. P. and Folgosa, F and Andrade, S. L. A. and Fauque, G and Pereira, AS and Tavares, P. and Calvete, JJ and Moura, I and Moura, JJG} } @article {4562, title = {A variable temperature spectroscopic study on Paracoccuspantotrophus pseudoazurin: protein constraints on the blue Cu site}, journal = {J Inorg Biochem}, volume = {103}, number = {10}, year = {2009}, note = {

Xie, XiangjinHadt, Ryan GPauleta, Sofia RGonzalez, Pablo JUn, SunMoura, IsabelSolomon, Edward IResearch Support, U.S. Gov{\textquoteright}t, Non-P.H.S.United StatesJournal of inorganic biochemistryJ Inorg Biochem. 2009 Oct;103(10):1307-13. doi: 10.1016/j.jinorgbio.2009.04.012. Epub 2009 May 7.

}, month = {Oct}, pages = {1307-13}, edition = {2009/06/02}, abstract = {

The blue or Type 1 (T1) copper site of Paracoccuspantotrophus pseudoazurin exhibits significant absorption intensity in both the 450 and 600 nm regions. These are sigma and pi S(Cys) to Cu(2+) charge transfer (CT) transitions. The temperature dependent absorption, EPR, and resonance Raman (rR) vibrations enhanced by these bands indicate that a single species is present at all temperatures. This contrasts the temperature dependent behavior of the T1 center in nitrite reductase [S. Ghosh, X. Xie, A. Dey, Y. Sun, C. Scholes, E. Solomon, Proc. Natl. Acad. Sci. 106 (2009) 4969-4974] which has a thioether ligand that is unconstrained by the protein. The lack of temperature dependence in the T1 site in pseudoazurin indicates the presence of a protein constraint similar to the blue Cu site in plastocyanin where the thioether ligand is constrained at 2.8 A. However, plastocyanin exhibits only pi CT. This spectral difference between pseudoazurin and plastocyanin reflects a coupled distortion of the site where the axial thioether in pseudoazurin is also constrained, but at a shorter Cu-S(Met) bond length. This leads to an increase in the Cu(2+)-S(Cys) bond length, and the site undergoes a partial tetragonal distortion in pseudoazurin. Thus, its ground state wavefunction has both sigma and pi character in the Cu(2+)-S(Cys) bond.

}, keywords = {Azurin/*chemistry, Binding Sites, Copper/*chemistry, Hot Temperature, Paracoccus pantotrophus/*chemistry, Plastocyanin/chemistry, Spectrum Analysis, Raman/methods}, isbn = {1873-3344 (Electronic)0162-0134 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/19481814}, author = {Xie, X. and Hadt, R. G. and Pauleta, S. R. and Gonzalez, P. J. and Un, S. and Moura, I and Solomon, E. I.} } @article {881, title = {Crystallization and crystallographic analysis of the apo form of the orange protein (ORP) from Desulfovibrio gigas}, journal = {Acta Crystallogr Sect F Struct Biol Cryst Commun}, volume = {65}, number = {Pt 7}, year = {2009}, note = {

Najmudin, ShabirBonifacio, CeciliaDuarte, Americo GPauleta, Sofia RMoura, IsabelMoura, Jose J GRomao, Maria JResearch Support, Non-U.S. Gov{\textquoteright}tEnglandActa crystallographica. Section F, Structural biology and crystallization communicationsActa Crystallogr Sect F Struct Biol Cryst Commun. 2009 Jul 1;65(Pt 7):730-2. Epub 2009 Jun 30.

}, month = {Jul 1}, pages = {730-2}, edition = {2009/07/04}, abstract = {

The orange-coloured protein (ORP) from Desulfovibrio gigas is a 12 kDa protein that contains a novel mixed-metal sulfide cluster of the type [S(2)MoS(2)CuS(2)MoS(2)]. Diffracting crystals of the apo form of ORP have been obtained. Data have been collected for the apo form of ORP to 2.25 A resolution in-house and to beyond 2.0 A resolution at ESRF, Grenoble. The crystals belonged to a trigonal space group, with unit-cell parameters a = 43, b = 43, c = 106 A.

}, keywords = {Apoproteins/*chemistry, Bacterial Proteins/*chemistry, Crystallization, Crystallography, X-Ray, Desulfovibrio gigas/*chemistry, Electrophoresis, Polyacrylamide Gel}, isbn = {1744-3091 (Electronic)1744-3091 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=PubMed\&dopt=Citation\&list_uids=19574652}, author = {Najmudin, S. and Bonifacio, C. and Duarte, A. G. and Pauleta, S. R. and Moura, I and Moura, J J and Romao, MJ} } @article {4567, title = {The electron transfer complex between D. gigas Superoxide Reductase and Rubredoxin}, journal = {Febs Journal}, volume = {276}, year = {2009}, note = {

Times Cited: 0 Almeida, R. Pauleta, S. Moura, I. Moura, J. J. G. 34th Congress of the Federation-of-European-Biochemical-Societies JUL 04-09, 2009 Prague, CZECH REPUBLIC Federat European Biochem Soc

}, month = {Jul}, pages = {128-128}, abstract = {n/a}, isbn = {1742-464X}, url = {://WOS:000267069900352}, author = {Almeida, R and Pauleta, S. and Moura, I and Moura, JJG} } @article {4565, title = {Molecular interactions/electron transfer protein complexes using Docking algorithms, spectroscopy (NMR) and site direct mutagenesis}, journal = {Febs Journal}, volume = {276}, year = {2009}, note = {

Times Cited: 0 Moura, J. Krippahl, L. Pauleta, S. Almeida, R. Del Acqua, S. 34th Congress of the Federation-of-European-Biochemical-Societies JUL 04-09, 2009 Prague, CZECH REPUBLIC Federat European Biochem Soc

}, month = {Jul}, pages = {11-11}, abstract = {n/a}, isbn = {1742-464X}, url = {://WOS:000267069900029}, author = {Moura, J and Krippahl, L. and Pauleta, S. and Almeida, R and Del Acqua, S.} } @article {4564, title = {Crystallization and crystallographic analysis of the apo form of the orange protein (ORP) from Desulfovibrio gigas. (vol F65, pg 730, 2009)}, journal = {Acta Crystallographica Section F-Structural Biology and Crystallization Communications}, volume = {65}, year = {2009}, note = {

Times Cited: 0 Najmudin, Shabir Bonifacio, Cecilia Duarte, Americo G. Pauleta, Sofia R. Moura, Isabel Moura, Jose J. G. Romao, Maria J. Part 8

}, month = {Aug}, pages = {856-856}, abstract = {n/a}, isbn = {1744-3091}, url = {://WOS:000268517300030}, author = {Najmudin, S. and Bonifacio, C. and Duarte, A. G. and Pauleta, S. R. and Moura, I and Moura, JJG and Romao, MJ} } @article {4570, title = {Electron transfer complex between nitrous oxide reductase and cytochrome c(552) from Pseudomonas nautica: Kinetic, nuclear magnetic resonance, and docking studies}, journal = {Biochemistry}, volume = {47}, number = {41}, year = {2008}, note = {

Times Cited: 9 Dell{\textquoteright}Acqua, Simone Pauleta, Sofia R. Monzani, Enrico Pereira, Alice S. Casella, Luigi Moura, Jose J. G. Moura, Isabel

}, month = {Oct}, pages = {10852-10862}, abstract = {

The multicopper enzyme nitrous oxide reductase (N2OR) catalyzes the final step of denitrification, the two-electron reduction of N2O to N-2. This enzyme is a functional homodimer containing two different multicopper sites: CuA and CuZ. CuA is a binuclear copper site that transfers electrons to the tetranuclear copper sulfide CuZ, the catalytic site. In this study, Pseudomonas nautica cytochrome C-552 was identified as the physiological electron donor. The kinetic data show differences when physiological and artificial electron donors are compared [cytochrome vs methylviologen (MV)]. In the presence of cytochrome c(552), the reaction rate is dependent on the ET reaction and independent of the N2O concentration. With MV, electron donation is faster than substrate reduction. From the study of cytochrome c(552) concentration dependence, we estimate the following kinetic parameters: K-mc512 = 50.2 +/- 9.0 mu M and V-maxc551 1.8 +/- 10.6 units/mg. The N2O concentration dependence indicates a K-mN2O of 14.0 +/- 2.9 mu M using MV as the electron donor. The pH effect on the kinetic parameters is different when MV or cytochrome c(552) is used as the electron donor (pK(a) = 6.6 or 8.3, respectively). The kinetic study also revealed the hydrophobic nature of the interaction, and direct electron transfer studies showed that CuA is the center that receives electrons from the physiological electron donor. The formation of the electron transfer complex was observed by H-1 NMR protein-protein titrations and was modeled with a molecular docking program (BiGGER). The proposed docked complexes corroborated the ET studies giving a large number of solutions in which cytochrome c(552) is placed near a hydrophobic patch located around the CuA center.

}, isbn = {0006-2960}, url = {://WOS:000259868300004}, author = {Dell{\textquoteright}acqua, S. and Pauleta, S. R. and Monzani, E and Pereira, AS and Casella, L. and Moura, JJG and Moura, I} } @article {4569, title = {Enzymatic activity mastered by altering metal coordination spheres}, journal = {Journal of Biological Inorganic Chemistry}, volume = {13}, number = {8}, year = {2008}, note = {

Times Cited: 7 Moura, Isabel Pauleta, Sofia R. Moura, Jose J. G.

}, month = {Nov}, pages = {1185-1195}, abstract = {

Metalloenzymes control enzymatic activity by changing the characteristics of the metal centers where catalysis takes place. The conversion between inactive and active states can be tuned by altering the coordination number of the metal site, and in some cases by an associated conformational change. These processes will be illustrated using heme proteins (cytochrome c nitrite reductase, cytochrome c peroxidase and cytochrome cd(1) nitrite reductase), non-heme proteins (superoxide reductase and [ NiFe]-hydrogenase), and copper proteins (nitrite and nitrous oxide reductases) as examples. These examples catalyze electron transfer reactions that include atom transfer, abstraction and insertion.

}, isbn = {0949-8257}, url = {://WOS:000260837700001}, author = {Moura, I and Pauleta, S. R. and Moura, JJG} } @article {4568, title = {Calcium-dependent heme structure in the reduced forms of the bacterial cytochrome c peroxidase from Paracoccus pantotrophus}, journal = {Biochemistry}, volume = {47}, number = {21}, year = {2008}, note = {

Times Cited: 3 Pauleta, Sofia R. Lu, Yi Goodhew, Celia F. Moura, Isabel Pettigrew, Graham W. Shelnutt, John A.

}, month = {May}, pages = {5841-5850}, abstract = {

This work reports for the first time a resonance Raman study of the mixed-valence and fully reduced forms of Paracoccus pantotrophus bacterial cytochrome c peroxidase. The spectra of the active mixed-valence enzyme show changes in the structure of the ferric peroxidatic heme compared to the fully oxidized enzyme; these differences are observed upon reduction of the electron-transferring heme and upon full occupancy of the calcium site. For the mixed-valence form in the absence of Ca2+, the peroxidatic heme is six-coordinate and low-spin on the basis of the frequencies of the structure-sensitive Raman lines: the enzyme is inactive. With added Ca2+, the peroxidatic heme is five-coordinate high-spin and active. The calcium-dependent spectral differences indicate little change in the conformation of the ferrous electron-transferring heme, but substantial changes in the conformation of the ferric peroxidatic heme. Structural changes associated with Ca2+ binding are indicated by spectral differences in the structure-sensitive marker lines, the out-of-plane low-frequency macrocyclic modes, and the vibrations associated with the heme substituents of that heme. The Ca2+-dependent appearance of a strong gamma(15) saddling-symmetry mode for the mixed-valence form is consistent with a strong saddling deformation in the active peroxidatic heme, a feature seen in the Raman spectra of other peroxidases. For the fully reduced form in the presence of Ca2+, the resonance Raman spectra show that the peroxidatic heme remains high-spin.

}, isbn = {0006-2960}, url = {://WOS:000256043200018}, author = {Pauleta, S. R. and Lu, Y. and Goodhew, C. F. and Moura, I and Pettigrew, G. W. and Shelnutt, J. A.} } @article {4571, title = {Benefits of membrane electrodes in the electrochemistry of metalloproteins: mediated catalysis of Paracoccus pantotrophus cytochrome c peroxidase by horse cytochrome c: a case study}, journal = {Journal of Biological Inorganic Chemistry}, volume = {13}, number = {5}, year = {2008}, note = {

Times Cited: 1 de Sousa, P. M. Paes Pauleta, S. R. Rodrigues, D. Goncalves, M. L. Simoes Pettigrew, G. W. Moura, I. Moura, J. J. G. dos Santos, M. M. Correia

}, month = {Jun}, pages = {779-787}, abstract = {

A comparative study of direct and mediated electrochemistry of metalloproteins in bulk and membrane-entrapped solutions is presented. This work reports the first electrochemical study of the electron transfer between a bacterial cytochrome c peroxidase and horse heart cytochrome c. The mediated catalysis of the peroxidase was analysed both using the membrane electrode configuration and with all proteins in solution. An apparent Michaelis constant of 66 +/- 4 and 42 +/- 5 mu M was determined at pH 7.0 and 0 M NaCl for membrane and bulk solutions, respectively. The data revealed that maximum activity occurs at 50 mM NaCl, pH 7.0, with intermolecular rate constants of (4.4 +/- 0.5) x 10(6) and (1.0 +/- 0.5) x 10(6) M(-1) s(-1) for membrane-entrapped and bulk solutions, respectively. The influence of parameters such as pH or ionic strength on the mediated catalytic activity was analysed using this approach, drawing attention to the fact that careful analysis of the results is needed to ensure that no artefacts are introduced by the use of the membrane configuration and/or promoters, and therefore the dependence truly reflects the influence of these parameters on the (mediated) catalysis. From the pH dependence, a pK of 7.5 was estimated for the mediated enzymatic catalysis.

}, isbn = {0949-8257}, url = {://WOS:000256320900013}, author = {de Sousa, P. M. P. and Pauleta, S. R. and Rodrigues, D. and Goncalves, M. L. S. and Pettigrew, G. W. and Moura, I and Moura, JJG and dos Santos, M. M. C.} } @article {4573, title = {Mediated catalysis of Paracoccus pantotrophus cytochrome c peroxidase by P-pantotrophus pseudoazurin: kinetics of intermolecular electron transfer}, journal = {Journal of Biological Inorganic Chemistry}, volume = {12}, number = {5}, year = {2007}, note = {

Times Cited: 9 de Sousa, P. M. Paes Pauleta, S. R. Goncalves, M. L. Simoes Pettigrew, G. W. Moura, I. dos Santos, M. M. Correia Moura, J. J. G.

}, month = {Jun}, pages = {691-698}, abstract = {

This work reports the direct electrochemistry of Paracoccus pantotrophus pseudoazurin and the mediated catalysis of cytochrome c peroxidase from the same organism. The voltammetric behaviour was examined at a gold membrane electrode, and the studies were performed in the presence of calcium to enable the peroxidase activation. A formal reduction potential, E (0){\textquoteright}, of 230 +/- 5 mV was determined for pseudoazurin at pH 7.0. Its voltammetric signal presented a pH dependence, defined by pK values of 6.5 and 10.5 in the oxidised state and 7.2 in the reduced state, and was constant up to 1 M NaCl. This small copper protein was shown to be competent as an electron donor to cytochrome c peroxidase and the kinetics of intermolecular electron transfer was analysed. A second-order rate constant of 1.4 +/- 0.2 x 10(5) M(-1) s(-1) was determined at 0 M NaCl. This parameter has a maximum at 0.3 M NaCl and is pH-independent between pH 5 and 9.

}, isbn = {0949-8257}, url = {://WOS:000247482600010}, author = {de Sousa, P. M. P. and Pauleta, S. R. and Goncalves, M. L. S. and Pettigrew, G. W. and Moura, I and dos Santos, M. M. C. and Moura, JJG} } @article {886, title = {NMR assignment of the apo-form of a Desulfovibrio gigas protein containing a novel Mo-Cu cluster}, journal = {Biomol NMR Assign}, volume = {1}, number = {1}, year = {2007}, note = {

Pauleta, Sofia RDuarte, Americo GCarepo, Marta SPereira, Alice STavares, PedroMoura, IsabelMoura, Jose J GResearch Support, Non-U.S. Gov{\textquoteright}tNetherlandsBiomolecular NMR assignmentsBiomol NMR Assign. 2007 Jul;1(1):81-3. Epub 2007 Jul 7.

}, month = {Jul}, pages = {81-3}, edition = {2007/07/01}, abstract = {

We report the 98\% assignment of the apo-form of an orange protein, containing a novel Mo-Cu cluster isolated from Desulfovibrio gigas. This protein presents a region where backbone amide protons exchange fast with bulk solvent becoming undetectable. These residues were assigned using 13C-detection experiments.

}, keywords = {Apoproteins/chemistry/genetics, Bacterial Proteins/*chemistry/genetics, Binding Sites, Carbon Isotopes, Copper/chemistry, Desulfovibrio gigas/*chemistry/genetics, Molecular Structure, Molybdenum/chemistry, Nuclear Magnetic Resonance, Biomolecular, Recombinant Proteins/chemistry/genetics}, isbn = {1874-270X (Electronic)}, url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=PubMed\&dopt=Citation\&list_uids=19636833}, author = {Pauleta, S. R. and Duarte, A. G. and Carepo, M. S. and Pereira, AS and Tavares, P. and Moura, I and Moura, J J} } @article {4575, title = {Kinetics studies of the superoxide-mediated electron transfer reactions between rubredoxin-type proteins and superoxide reductases}, journal = {Journal of Biological Inorganic Chemistry}, volume = {11}, number = {4}, year = {2006}, note = {

Times Cited: 11 Auchere, F Pauleta, SR Tavares, P Moura, I Moura, JJG

}, month = {Jun}, pages = {433-444}, abstract = {

In this work we present a kinetic study of the superoxide-mediated electron transfer reactions between rubredoxin-type proteins and members of the three different classes of superoxide reductases (SORs). SORs from the sulfate-reducing bacteria Desulfovibrio vulgaris (Dv) and D. gigas (Dg) were chosen as prototypes of classes I and II, respectively, while SOR from the syphilis spyrochete Treponema pallidum (Tp) was representative of class III. Our results show evidence for different behaviors of SORs toward electron acceptance, with a trend to specificity for the electron donor and acceptor from the same organism. Comparison of the different k (app) values, 176.9 +/- 25.0 min(-1) in the case of the Tp/Tp electron transfer, 31.8 +/- 3.6 min(-1) for the Dg/Dg electron transfer, and 6.9 +/- 1.3 min(-1) for Dv/Dv, could suggest an adaptation of the superoxide-mediated electron transfer efficiency to various environmental conditions. We also demonstrate that, in Dg, another iron-sulfur protein, a desulforedoxin, is able to transfer electrons to SOR more efficiently than rubredoxin, with a k (app) value of 108.8 +/- 12.0 min(-1), and was then assigned as the potential physiological electron donor in this organism.

}, isbn = {0949-8257}, url = {://WOS:000237340800005}, author = {Auchere, F and Pauleta, S. R. and Tavares, P. and Moura, I and Moura, JJG} } @article {4574, title = {Structure and mechanism in the bacterial dihaem cytochrome c peroxidases}, journal = {Journal of Inorganic Biochemistry}, volume = {100}, number = {4}, year = {2006}, note = {

Times Cited: 29 Pettigrew, Graham W. Echalier, Aude Pauleta, Sofia R.

}, month = {Apr}, pages = {551-567}, abstract = {

The bacterial cytochroine c peroxidases contain an electron-transferring haem c (E) and a peroxidatic haem c (P). Many are isolated in an inactive oxidised state. Reduction of the E baem promotes Ca2+-dependent spin state and coordination changes at the P haem rendering it accessible to ligand. Recent crystallographic work on the oxidised and mixed valence enzymes has suggested a mechanism by which an electron entering the E haem remotely triggers this activation of the P haem. Binding of hydrogen peroxide at the activated P haem leads to an intermediate catalytic form containing two oxidising equivalents, one of which is a ferryl oxene. This form of the enzyme is then reduced by two single electron transfers to the E haem delivered by small redox proteins such as cytochromes or cupredoxins. The binding of these small redox proteins is dominated by global electrostatic forces but the interfaces of the electron transfer complexes that are formed are largely hydrophobic and relatively non-specific. These features allow very high electron transfer rates in the steady state. (c) 2006 Elsevier Inc. All rights reserved.

}, isbn = {0162-0134}, url = {://WOS:000237829000014}, author = {Pettigrew, G. W. and Echalier, A. and Pauleta, S. R.} } @article {4576, title = {Paracoccus pantotrophus pseudoazurin is an electron donor to cytochrome c peroxidase}, journal = {Biochemistry}, volume = {43}, number = {35}, year = {2004}, note = {

Pauleta, Sofia RGuerlesquin, FrancoiseGoodhew, Celia FDevreese, BartVan Beeumen, JozefPereira, Alice SMoura, IsabelPettigrew, Graham WResearch Support, Non-U.S. Gov{\textquoteright}tUnited StatesBiochemistryBiochemistry. 2004 Sep 7;43(35):11214-25.

}, month = {Sep 7}, pages = {11214-25}, edition = {2004/09/16}, abstract = {

The gene for pseudoazurin was isolated from Paracoccus pantotrophus LMD 52.44 and expressed in a heterologous system with a yield of 54.3 mg of pure protein per liter of culture. The gene and protein were shown to be identical to those from P. pantotrophus LMD 82.5. The extinction coefficient of the protein was re-evaluated and was found to be 3.00 mM(-1) cm(-1) at 590 nm. It was confirmed that the oxidized protein is in a weak monomer/dimer equilibrium that is ionic-strength-dependent. The pseudoazurin was shown to be a highly active electron donor to cytochrome c peroxidase, and activity showed an ionic strength dependence consistent with an electrostatic interaction. The pseudoazurin has a very large dipole moment, the vector of which is positioned at the putative electron-transfer site, His81, and is conserved in this position across a wide range of blue copper proteins. Binding of the peroxidase to pseudoazurin causes perturbation of a set of NMR resonances associated with residues on the His81 face, including a ring of lysine residues. These lysines are associated with acidic residues just back from the rim, the resonances of which are also affected by binding to the peroxidase. We propose that these acidic residues moderate the electrostatic influence of the lysines and so ensure that specific charge interactions do not form across the interface with the peroxidase.

}, keywords = {Azurin/*analogs \& derivatives/biosynthesis/genetics/*metabolism, Copper/chemistry/metabolism, Cytochrome-c Peroxidase/chemistry/*metabolism, Dimerization, Electron Transport, Gene Expression Regulation, Bacterial, Hydrophobic and Hydrophilic Interactions, Kinetics, Lysine/metabolism, Magnetic Resonance Spectroscopy, Metalloproteins/chemistry/metabolism, Models, Molecular, Oxidation-Reduction, Paracoccus pantotrophus/*enzymology, Peptide Mapping, Protein Binding, Static Electricity, Substrate Specificity}, isbn = {0006-2960 (Print)0006-2960 (Linking)}, url = {http://www.ncbi.nlm.nih.gov/pubmed/15366931}, author = {Pauleta, S. R. and Guerlesquin, F. and Goodhew, C. F. and Devreese, B and VanBeeumen, J and Pereira, AS and Moura, I and Pettigrew, G. W.} } @article {4577, title = {A copper protein and a cytochrome bind at the same site on bacterial cytochrome c peroxidase}, journal = {Biochemistry}, volume = {43}, number = {46}, year = {2004}, note = {

Times Cited: 16 Pauleta, SR Cooper, A Nutley, M Errington, N Harding, S Guerlesquin, F Goodhew, CF Moura, I Moura, JJG Pettigrew, GW

}, month = {Nov}, pages = {14566-14576}, abstract = {

Pseudoazurin binds at a single site on cytochrome c peroxidase from Paracoccus pantotrophus with a K-d of 16.4 muM at 25 degreesC, pH 6.0, in an endothermic reaction that is driven by a large entropy change. Sedimentation velocity experiments confirmed the presence of a single site, although results at higher pseudoazurin concentrations are complicated by the dimerization of the protein. Microcalorimetry, ultracentrifugation, and H-1 NMR spectroscopy studies in which cytochrome c550, pseudoazurin, and cytochrome c peroxidase were all present could be modeled using a competitive binding algorithm. Molecular docking simulation of the binding of pseudoazurin to the peroxidase in combination with the chemical shift perturbation pattern for pseudoazurin in the presence of the peroxidase revealed a group of solutions that were situated close to the electron-transferring heme with Cu-Fe distances of about 14 Angstrom. This is consistent with the results of H-1 NMR spectroscopy, which showed that pseudoazurin binds closely enough to the electron - transferring heme of the peroxidase to perturb its set of heme methyl resonances. We conclude that cytochrome c550 and pseudoazurin bind at the same site on the cytochrome c peroxidase and that the pair of electrons required to restore the enzyme to its active state after turnover are delivered one-by-one to the electron-transferring heme.

}, isbn = {0006-2960}, url = {://WOS:000225172800007}, author = {Pauleta, S. R. and Cooper, A. and Nutley, M. and Errington, N. and Harding, S. and Guerlesquin, F. and Goodhew, C. F. and Moura, I and Moura, JJG and Pettigrew, G. W.} } @article {4578, title = {Electron transfer complexes of cytochrome c peroxidase from Paracoccus denitrificans containing more than one cytochrome}, journal = {Biochemistry}, volume = {42}, number = {41}, year = {2003}, note = {

Times Cited: 11 Pettigrew, GW Pauleta, SR Goodhew, CF Cooper, A Nutley, M Jumel, K Harding, SE Costa, C Krippahl, L Moura, I Moura, J

}, month = {Oct}, pages = {11968-11981}, abstract = {

According to the model proposed in previous papers [Pettigrew, G. W., Prazeres, S., Costa, C., Palma, N., Krippahl, L., and Moura, J. J. (1999) The structure of an electron-transfer complex containing a cytochrome c and a peroxidase, J. Biol. Chem. 274, 11383-11389; Pettigrew, G. W., Goodhew, C. F., Cooper, A., Nutley, M., Jumel, K., and Harding, S. E. (2003) Electron transfer complexes of cytochrome c peroxidase from Paracoccus denitrificans, Biochemistry 42, 2046-2055], cytochrome c peroxidase of Paracoccus denitrificans can accommodate horse cytochrome c and Paracoccus cytochrome c(550) at different sites on its molecular surface. Here we use H-1 NMR spectroscopy, analytical ultracentrifugation, molecular docking simulation, and microcalorimetry to investigate whether these small cytochromes can be accommodated simultaneously in the formation of a ternary complex. The pattern of perturbation of heme methyl and methionine methyl resonances in binary and ternary solutions shows that a ternary complex can be formed, and this is confirmed by the increase in the sedimentation coefficient upon addition of horse cytochrome c to a solution in which cytochrome c(550) fully occupies its binding site on cytochrome c peroxidase. Docking experiments in which favored binary solutions of cytochrome, c(550) bound to cytochrome c peroxidase act as targets for horse cytochrome c and the reciprocal experiments in which favored binary solutions of horse cytochrome c bound to cytochrome c peroxidase act as targets for cytochrome c(550) show that the enzyme can accommodate both cytochromes at the same time on adjacent sites. Microcalorimetric titrations are difficult to interpret but are consistent with a weakened binding of horse cytochrome c to a binary complex of cytochrome c peroxidase and cytochrome c(550) and binding of cytochrome c(550) to the cytochrome c peroxidase that is affected little by the presence of horse cytochrome c in the other site. The presence of a substantial capture surface for small cytochromes on the cytochrome c peroxidase has implications for rate enhancement mechanisms which ensure that the two electrons required for re-reduction of the enzyme after reaction with hydrogen peroxide are delivered efficiently.

}, isbn = {0006-2960}, url = {://WOS:000186007000010}, author = {Pettigrew, G. W. and Pauleta, S. R. and Goodhew, C. F. and Cooper, A. and Nutley, M. and Jumel, K. and Harding, S. E. and Costa, C and Krippahl, L. and Moura, I and Moura, J} } @article {4579, title = {Structural changes in the calcium-dependent activation of the di-heme cytochrome c peroxidase of Paracoccus pantotrophus}, journal = {Biophysical Journal}, volume = {82}, number = {1}, year = {2002}, note = {

Times Cited: 0 Pauleta, SR Lu, Y Goodhew, CF Qiu, Y Moura, I Pettigrew, GW Shelnutt, JA Part 2

}, month = {Jan}, pages = {14A-14A}, abstract = {n/a}, isbn = {0006-3495}, url = {://WOS:000173252700065}, author = {Pauleta, S. R. and Lu, Y. and Goodhew, C. F. and Qiu, Y. and Moura, I and Pettigrew, G. W. and Shelnutt, J. A.} } @article {4582, title = {Calcium-dependent conformation of a heme and fingerprint peptide of the diheme cytochrome c peroxidase from Paracoccus pantotrophus}, journal = {Biochemistry}, volume = {40}, number = {22}, year = {2001}, note = {

Times Cited: 8 Pauleta, SR Lu, Y Goodhew, CF Moura, I Pettigrew, GW Shelnutt, JA

}, month = {Jun}, pages = {6570-6579}, abstract = {

The structural changes in the heme macrocycle and substituents caused by binding of Ca2+ to the diheme cytochrome c peroxidase from Paracoccus pantotrophus were clarified by resonance Raman spectroscopy of the inactive fully oxidized form of the enzyme. The changes in the macrocycle vibrational modes are consistent with a Ca2+-dependent increase in the out-of-plane distortion of the low-potential heme, the proposed peroxidatic heme. Most of the increase in out-of-plane distortion occurs when the high-affinity site I is occupied, but a small further increase in distortion occurs when site II is also occupied by Ca2+ or Mg2+. This increase in the heme distortion explains the red shift in the Soret absorption band that occurs upon Ca2+ binding. Changes also occur in the low-frequency substituent modes of the heme, indicating that a structural change in the covalently attached fingerprint pentapeptide of the LP heme occurs upon Ca2+ binding to site I. These structural changes may lead to loss of the sixth ligand at the peroxidatic heme in the semireduced form of the enzyme and activation.

}, isbn = {0006-2960}, url = {://WOS:000169232200003}, author = {Pauleta, S. R. and Lu, Y. and Goodhew, C. F. and Moura, I and Pettigrew, G. W. and Shelnutt, J. A.} } @article {4581, title = {Cytochrome c peroxidase and its redox partners - binary and ternary complexes}, journal = {Journal of Inorganic Biochemistry}, volume = {86}, number = {1}, year = {2001}, note = {

Times Cited: 0 Pettigrew, G Goodhew, C Pauleta, S Costa, C Moura, I Moura, J Palma, N Krippahl, L Jumel, K Harding, S Cooper, A

}, month = {Aug}, pages = {86-86}, abstract = {n/a}, isbn = {0162-0134}, url = {://WOS:000170467300151}, author = {Pettigrew, G. and Goodhew, C. and Pauleta, S. and Costa, C and Moura, I and Moura, J and Palma, N. and Krippahl, L. and Jumel, K. and Harding, S. and Cooper, A.} } @article {4583, title = {Cytochrome c peroxidase as a model system to study electron transfer complexes}, journal = {Journal of Inorganic Biochemistry}, volume = {86}, number = {1}, year = {2001}, note = {

Times Cited: 0 Pauleta, SR Costa, C Cooper, A Moura, I Pettigrew, GW

}, month = {Aug}, pages = {374-374}, abstract = {n/a}, isbn = {0162-0134}, url = {://WOS:000170467300718}, author = {Pauleta, S. R. and Costa, C and Cooper, A. and Moura, I and Pettigrew, G. W.} } @article {4580, title = {Structural changes associated with calcium-dependent activation of the di-heme cytochrome c peroxidase of Paracoccus pantotrophus}, journal = {Journal of Inorganic Biochemistry}, volume = {86}, number = {1}, year = {2001}, note = {

Times Cited: 0 Qiu, Y Pauleta, SR Lu, Y Goodhew, CF Moura, I Pettigrew, GW Shelnutt, JA

}, month = {Aug}, pages = {386-386}, abstract = {n/a}, isbn = {0162-0134}, url = {://WOS:000170467300741}, author = {Qiu, Y. and Pauleta, S. R. and Lu, Y. and Goodhew, C. F. and Moura, I and Pettigrew, G. W. and Shelnutt, J. A.} }