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Auteur : Grafiati
Publié le 10 mars 2023
Mis à jour le 11 mars 2023

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1

Cai, Lisheng, Brent M. Segal, Jeffrey R. Long, Michael J. Scott et R. H. Holm. « Octanuclear Iron-Sulfur Clusters with Symmetrically Coupled Fe4S4 and Fe4S5 Cores ». Journal of the American Chemical Society 117, no 34 (août 1995) : 8863–64. http://dx.doi.org/10.1021/ja00139a025.

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2

Schwarz, Michael, et Caroline Röhr. « Cs8[Fe4S10] and Cs7[Fe4S8], Two New Sulfido Ferrates with Different Tetrameric anions ». Inorganic Chemistry 54, no 3 (16 décembre 2014) : 1038–48. http://dx.doi.org/10.1021/ic502382v.

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3

Schwarz, Michael, et Caroline Roehr. « ChemInform Abstract : Cs8[Fe4S10] and Cs7[Fe4S8], Two New Sulfido Ferrates with Different Tetrameric Anions. » ChemInform 46, no 16 (avril 2015) : no. http://dx.doi.org/10.1002/chin.201516005.

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4

Belinskii, Moshe, Ivano Bertini, Oleg Galas et Claudio Luchinat. « The Electronic Structure of the Fe4S3+4Cluster in Proteins : The Importance of Double Exchange Parameter ». Zeitschrift für Naturforschung A 50, no 1 (1 janvier 1995) : 75–80. http://dx.doi.org/10.1515/zna-1995-0110.

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The recently obtained Mössbauer and EPR parameters of the Fe4S43+ polymetallic center in the High Potential Iron-Sulfur Protein (HiPIP) II from E. halophila have been reproduced with models based on pure Heisenberg exchange. The role of double exchange versus ./-inequivalence is discussed. An evaluation of the upper limit of the double exchange parameter in the Fe4S43+ bimetallic center is also presented. The present calculations shed further light on the electronic structure of the Fe4S43+ center.
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5

Tyson, Marni A., Konstantinos D. Demadis et Dimitri Coucouvanis. « Uncharged Mixed-Ligand Clusters with the [Fe4S4]+ and [Fe4S4]2+ Cores. Synthesis, Structural Characterization, and Properties of the Fe4S4X(tBu3P)3 (X = Cl, Br, I) and Fe4S4(SPh)2(tBu3P)2 Cubanes ». Inorganic Chemistry 34, no 18 (août 1995) : 4519–20. http://dx.doi.org/10.1021/ic00122a002.

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6

Harmjanz, M., C. Junghans, U. A. Opitz, B. Bahlmann et S. Pohl. « Neue Synthesewege zu neutralen gemischtsubstituierten Eisen-Schwefel-Clustern / Novel Synthetic Pathways to Neutral Mixed-Ligand Iron-Sulfur Clusters ». Zeitschrift für Naturforschung B 51, no 7 (1 juillet 1996) : 1040–48. http://dx.doi.org/10.1515/znb-1996-0722.

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The reaction of [Fe(NiSiMe3)2)2] with thiols RSH, elemental sulfur, and neutral ligands L (with sulfur donor atoms, e. g. thiourea derivatives) gives [Fe4S4(SR)2L2] clusters in high yields. The structure of [Fe4S4(2.4.6-(C3H7)3C6H2-S)2(dpdmi)2] (dpdmi: diisopropyldimethyl- imidazolthion) was determined by X-ray crystallography.When [Fe4S4I4]2- is reacted with a large excess of PMePh2 or PMe2Ph [F6S6I2(PMePh2)4] and [Fe6S6l2(PMe2Ph)4]. respectively, are obtained in nearly quantitative yield. Basket-like structures of the [Fe6S6]2+ cores were detected by X-ray structure analysis. While [Fe4S4(SR)4]2- clusters do not react with phosphanes at ambient temperature 2:2 functional­ized species like [Fe4S4(SR)2(tmtu)2] lead to basket-type clusters [Fe6S6(SR)2(PR3)4].
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7

Moriarty, Nigel W., et Paul D. Adams. « Iron–sulfur clusters have no right angles ». Acta Crystallographica Section D Structural Biology 75, no 1 (1 janvier 2019) : 16–20. http://dx.doi.org/10.1107/s205979831801519x.

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Accurate geometric restraints are vital in the automation of macromolecular crystallographic structure refinement. A set of restraints for the Fe4S4 cubane-type cluster was created using the Cambridge Structural Database (CSD) and high-resolution structures from the Protein Data Bank. Geometries from each source were compared and pairs of refinements were performed to validate these new restraints. In addition to the restraints internal to the cluster, the CSD was mined to generate bond and angle restraints to be applied to the most common linking motif for Fe4S4: coordination of the four Fe atoms to the side-chain sulfurs of four cysteine residues. Furthermore, computational tools were developed to assist researchers when refining Fe4S4-containing proteins.
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8

Liu, Jian She, Yan Fei Zhang, Mei Mei Geng, Jia Zeng et Guan Zhou Qiu. « Research on isc Operon in Acidithiobacillus ferrooxidans ATCC 23270 ». Advanced Materials Research 20-21 (juillet 2007) : 509–12. http://dx.doi.org/10.4028/www.scientific.net/amr.20-21.509.

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The highly conserved operon iron–sulfur cluster (iscSUA) is essential for the general biogenesis and transfer of iron–sulfur proteins in bacteria. In this study, expression, purification and characterization of the proteins of the isc operon (iscSUA) of Acidithiobacillus ferrooxidans ATCC 23270 was studied. Assembly and transfer of [Fe4S4] in vitro during the isc proteins and other iron sulfur proteins was studied in order to detect the pathway and mechanism of [Fe4S4] assembly and transfer in vivo. The [Fe4S4] cluster was successfully assembled in iron-sulfur proteins in vitro in the presence of Fe2+ and sulfide, and it was successfully transferred from IscA or IscU to iron- sulfur proteins. Our results support and extend certain models of iron-sulfur clusters assembly and transfer.
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9

Das, Diganta Kumar, Dhanada Sarmah et Raben Ch Roy. « Significant effect of charge microenvironment on the redox potential of [Fe4Se4(SPh)4]2− in solution and inside film ». Canadian Journal of Chemistry 92, no 7 (juillet 2014) : 625–28. http://dx.doi.org/10.1139/cjc-2013-0586.

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Through this work, we have shown that both the nature and the compactness of charge of the microenvironment around the [Fe4Se4(SPh)4]2−/3− couple are important in determining its redox potential. The redox potential of the [Fe4Se4(SPh)4]2−/3− couple has been measured in pure dimethylformamide (DMF), DMF added with surfactants of different charges, and also in positive surfactant film on an electrode surface. The redox potential becomes 0.090 V positive when the solution microenvironment is made positive compared to that in DMF. On the other hand, if the microenvironment is made positive and static (in the form of a positive film), the positive shift in the potential is 0.265 V, and compactness of charge induced an extra 0.175 V positive shift in the potential.
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10

Barber, M. J., V. Pollock et J. T. Spence. « Microcoulometric analysis of trimethylamine dehydrogenase ». Biochemical Journal 256, no 2 (1 décembre 1988) : 657–59. http://dx.doi.org/10.1042/bj2560657.

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Trimethylamine dehydrogenase, which contains one covalently bound 6-S-cysteinyl-FMN and one Fe4S4 cluster per subunit of molecular mass 83,000 Da, was purified to homogeneity from the methylotrophic bacterium W3A1. Microcoulometry at pH 7 in 50 mM-Mops buffer containing 0.1 mM-EDTA and 0.1 M-KCl revealed that the native enzyme required the addition of 3 reducing equivalents per subunit for complete reduction. In contrast, under identical conditions the phenylhydrazine-inhibited enzyme required the addition of 0.9 reducing equivalent per subunit with a midpoint potential of +110 mV. Least-squares analysis of the microcoulometric data obtained for the native enzyme, assuming uptake of 1 electron by Fe4S4 and 2 electrons by FMN, indicated midpoint potentials of +44 mV and +36 mV for the FMN/FMN.- and FMN.-/FMNH2 couples respectively and +102 mV for reduction of the Fe4S4 cluster.
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11

Harmjanz, Michael, Wolfgang Saak, Detlev Haase et Siegfried Pohl. « Aryl isonitrile binding to [Fe4S4] clusters : formation of [Fe4S4]+ and [{Fe4S4}2]2 cores ». Chemical Communications, no 10 (1997) : 951–52. http://dx.doi.org/10.1039/a700613f.

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12

Hirano, Yu, Kazuki Takeda, Kazuo Kurihara, Taro Tamada et Kunio Miki. « Ultra-high resolution structure of high-potential iron-sulfur protein ». Acta Crystallographica Section A Foundations and Advances 70, a1 (5 août 2014) : C1201. http://dx.doi.org/10.1107/s2053273314087981.

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It is important for understanding the electron transfer reaction to include the information about valence shell electrons and hydrogen atoms into crystal structure refinement. High-potential iron-sulfur protein (HiPIP) possesses a Fe4S4 cluster which exhibits +2/+3 redox states and acts as an electron carrier from cytochrome bc1 complex to the reaction center complex in photosynthetic purple bacteria. We have reported the X-ray crystal structure of HiPIP from Thermochtomatium tepidum at 0.72 Å resolution (1). Recently, we have successfully collected 0.48 Å resolution data of HiPIP using high-energy X-rays (31 keV) in BL41XU beamline of SPring-8. We performed multipolar refinement with the MoPro program (2) to consider valence shell electrons in the structure refinement of HiPIP. Refinement of multipolar parameters was applied to atoms of single conformational residues, water molecules with two hydrogen atoms, and the Fe4S4 cluster. After multipolar refinement, the deformation map clearly displays the distribution of valence shell electrons such as lone-pair electrons of carbonyl oxygen atoms, bonding electrons in aromatic rings, and d-orbital electrons of Fe atoms in the Fe4S4 cluster. The deformation map also indicates electrostatic interactions between the S atoms of Fe4S4-(Cys-Sγ)4 and protein environment. In addition, we performed preliminary neutron diffraction experiment at iBIX beamline of Japan Proton Accelerator Research Complex (J-PARC) and observed diffraction spots up to 1.17 Å resolution using HiPIP crystal with the size of 2.3 mm3. In the multipolar refinement, the positions of hydrogen atoms were fixed to the standard bond distances derived from neutron crystal structures of small molecules and atomic displacement parameters of hydrogen atoms were constrained to 1.2 or 1.5 fold of their root atoms. Therefore, a high resolution neutron structure of HiPIP will improve the results obtained from the multipolar refinement.
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13

Scott, Thomas A., et Hong-Cai Zhou. « The First All-Cyanide Fe4S4 Cluster : [Fe4S4(CN)4]3 ? » Angewandte Chemie International Edition 43, no 42 (25 octobre 2004) : 5628–31. http://dx.doi.org/10.1002/anie.200460879.

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14

Scott, Thomas A., et Hong-Cai Zhou. « The First All-Cyanide Fe4S4 Cluster : [Fe4S4(CN)4]3 ? » Angewandte Chemie 116, no 42 (25 octobre 2004) : 5746–49. http://dx.doi.org/10.1002/ange.200460879.

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15

Pohl, Siegfried, et Wolfgang Saak. « Zur strukturellen Verzerrung von Fe4S4I42- -Clustern durch Iod-Iod-Kon Die Kristallstrukturen von (Ph4P)2Fe4S4I4 und (Me3NCH2Ph)2Fe4S4I4 / Structural Distortion of Fe4S4I22- Clusters through Iodine-Iodine Contacts : Crystal Structures of (Ph4P)2Fe4S4I4 and (Me3NCH2Ph)2Fe4S4I4 ». Zeitschrift für Naturforschung B 43, no 4 (1 avril 1988) : 457–62. http://dx.doi.org/10.1515/znb-1988-0412.

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AbstractThe structures of (Ph4P)2Fe4S4I4 (1) and (Me3NCH2Ph)2Fe4S4I4 (2) were determined from single crystal X-ray diffraction data.1 crystallizes in the tetragonal space group I41/a with a = 1088.3(1) and c = 4540.3(2) pm. Z = 4.2: Monoclinic, space group Cc. a = 1332.0(2), b = 1513.8(3), c = 1755.1(3) pm, β = 96.69(1)°, Z = 4.In 1 the anion Fe4S4I42- has imposed S4 symmetry with four short (226.2 pm) and eight long (228.1 and 228.4 pm) Fe-S distances parallel and perpendicular, respectively, to the crystallo­graphic 4̃ axis. The Fe-Fe distances were found to be 274.3 and 275.5 pm (Fe-I 254.1 p0m).In (Me3NCH2Ph)2Fe4S4I4 the [Fe4S4]2+ cluster also exhibits a slightly compressed tetragonal core structure but the core distortions are larger and less regular than in 1 (Fe-S distances from 224.6 to 232.9 pm, Fe-Fe distances from 269.6 to 275.9 pm, Fe-I distances from 249.5 to 255.7 pm).In addition there are in 2 iodine-iodine interactions between the anions with an I-I distance of 391.7 pm. These weak attractive forces seem to be the reason for the rather large and hitherto in [Fe4S4] clusters with four identical ligands unobserved distortion of the Fe4S4 core.
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Sickerman, Nathaniel S., Lee A. Rettberg, Chi Chung Lee, Yilin Hu et Markus W. Ribbe. « Cluster assembly in nitrogenase ». Essays in Biochemistry 61, no 2 (9 mai 2017) : 271–79. http://dx.doi.org/10.1042/ebc20160071.

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The versatile enzyme system nitrogenase accomplishes the challenging reduction of N2and other substrates through the use of two main metalloclusters. For molybdenum nitrogenase, the catalytic component NifDK contains the [Fe8S7]-core P-cluster and a [MoFe7S9C-homocitrate] cofactor called the M-cluster. These chemically unprecedented metalloclusters play a critical role in the reduction of N2, and both originate from [Fe4S4] clusters produced by the actions of NifS and NifU. Maturation of P-cluster begins with a pair of these [Fe4S4] clusters on NifDK called the P*-cluster. An accessory protein NifZ aids in P-cluster fusion, and reductive coupling is facilitated by NifH in a stepwise manner to form P-cluster on each half of NifDK. For M-cluster biosynthesis, two [Fe4S4] clusters on NifB are coupled with a carbon atom in a radical-SAM dependent process, and concomitant addition of a ‘ninth’ sulfur atom generates the [Fe8S9C]-core L-cluster. On the scaffold protein NifEN, L-cluster is matured to M-cluster by the addition of Mo and homocitrate provided by NifH. Finally, matured M-cluster in NifEN is directly transferred to NifDK, where a conformational change locks the cofactor in place. Mechanistic insights into these fascinating biosynthetic processes are detailed in this chapter.
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17

NOODLEMAN, L. « ChemInform Abstract : Exchange Coupling and Resonance Delocalization in Reduced (Fe4S4)+ and (Fe4Se4)+ Clusters. Part 1. Basic Theory of Spin-State Energies and EPR and Hyperfine Properties ». ChemInform 22, no 18 (23 août 2010) : no. http://dx.doi.org/10.1002/chin.199118013.

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18

Liu, Jian, Matthew S. Kelley, Weiqiang Wu, Abhishek Banerjee, Alexios P. Douvalis, Jinsong Wu, Yongbo Zhang, George C. Schatz et Mercouri G. Kanatzidis. « Nitrogenase-mimic iron-containing chalcogels for photochemical reduction of dinitrogen to ammonia ». Proceedings of the National Academy of Sciences 113, no 20 (2 mai 2016) : 5530–35. http://dx.doi.org/10.1073/pnas.1605512113.

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A nitrogenase-inspired biomimetic chalcogel system comprising double-cubane [Mo2Fe6S8(SPh)3] and single-cubane (Fe4S4) biomimetic clusters demonstrates photocatalytic N2 fixation and conversion to NH3 in ambient temperature and pressure conditions. Replacing the Fe4S4 clusters in this system with other inert ions such as Sb3+, Sn4+, Zn2+ also gave chalcogels that were photocatalytically active. Finally, molybdenum-free chalcogels containing only Fe4S4 clusters are also capable of accomplishing the N2 fixation reaction with even higher efficiency than their Mo2Fe6S8(SPh)3-containing counterparts. Our results suggest that redox-active iron-sulfide–containing materials can activate the N2 molecule upon visible light excitation, which can be reduced all of the way to NH3 using protons and sacrificial electrons in aqueous solution. Evidently, whereas the Mo2Fe6S8(SPh)3 is capable of N2 fixation, Mo itself is not necessary to carry out this process. The initial binding of N2 with chalcogels under illumination was observed with in situ diffuse-reflectance Fourier transform infrared spectroscopy (DRIFTS). 15N2 isotope experiments confirm that the generated NH3 derives from N2. Density functional theory (DFT) electronic structure calculations suggest that the N2 binding is thermodynamically favorable only with the highly reduced active clusters. The results reported herein contribute to ongoing efforts of mimicking nitrogenase in fixing nitrogen and point to a promising path in developing catalysts for the reduction of N2 under ambient conditions.
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19

Noodleman, Louis. « Exchange coupling and resonance delocalization in reduced iron-sulfur [Fe4S4]+ and iron-selenium [Fe4Se4]+ clusters. 1. Basic theory of spin-state energies and EPR and hyperfine properties ». Inorganic Chemistry 30, no 2 (janvier 1991) : 246–56. http://dx.doi.org/10.1021/ic00002a019.

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20

Kuroda, Yasuhisa, Yoro Sasaki, Yasushi Shiroiwa et Iwao Tabushi. « Cyclodextrin sandwiched Fe4S4 cluster ». Journal of the American Chemical Society 110, no 12 (juin 1988) : 4049–50. http://dx.doi.org/10.1021/ja00220a060.

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NOODLEMAN, L. « ChemInform Abstract : Exchange Coupling and Resonance Delocalization in Reduced (Fe4S4)+ and (Fe4Se4)+ Clusters. Part 2. A Generalized Nonlinear Model for Spin- State Energies and EPR and Hyperfine Properties ». ChemInform 22, no 18 (23 août 2010) : no. http://dx.doi.org/10.1002/chin.199118014.

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22

Ohki, Y., K. Tanifuji, N. Yamada, M. Imada, T. Tajima et K. Tatsumi. « Synthetic analogues of [Fe4S4(Cys)3(His)] in hydrogenases and [Fe4S4(Cys)4] in HiPIP derived from all-ferric [Fe4S4 4] ». Proceedings of the National Academy of Sciences 108, no 31 (18 juillet 2011) : 12635–40. http://dx.doi.org/10.1073/pnas.1106472108.

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23

Saak, Wolfgang, et Siegfried Pohl. « Fe4S4l2(SPPh3)2 : ein neutraler, gemischt substituierter Eisen-Schwefel-Cluster / Fe4S4I2(SPPh3)2 : a Neutral, Mixed Terminal Ligand Iron-Sulfur Cluster ». Zeitschrift für Naturforschung B 43, no 7 (1 juillet 1988) : 813–17. http://dx.doi.org/10.1515/znb-1988-0705.

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Fe4S4I2(SPPh3)2 (1) was prepared by the reaction of Fe(THF)6Fe4S4I4 (THF = C4H8O). SPPh,. and sulfur in toluene and CH2Cl2. 1 has a lower stability than Fe4S4I42- and decomposes in solvents like THF and CH3CN. The crystal structure of 1 was determined from single crystal X-ray diffraction data. The compound crystallizes in the triclinic space group P1̄ with a = 1025.5(1). b = 1082.4(1), c = 2135.5(3) pm. α = 89.82(1), β - 77.37(1), γ = 73.56(1)°, V = 2214.1×106 pm3 and Z = 2. The [Fe4S4]2+ core of 1 exhibits a slight tetragonal distortion. The mean Fe-S and Fe-Fe distances were found to be 227.6 (225.8-228.7) pm and 273.3 (272.9-274.4) pm, respectively. The Fe-SPPh3 distances (231.6 and 232.1 pm) are longer than the terminal Fe-S bonds in RS coordinated [Fe4S4] clusters. The Fe-I bonds are found at 251.6 and 251.8 pm. respectively.
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24

Noodleman, Louis. « Exchange coupling and resonance delocalization in reduced iron-sulfur [Fe4S4]+ and iron-selenium [Fe4Se4]+ clusters. 2. A generalized nonlinear model for spin-state energies and EPR and hyperfine properties ». Inorganic Chemistry 30, no 2 (janvier 1991) : 256–64. http://dx.doi.org/10.1021/ic00002a020.

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25

Lui, S. M., A. Soriano et J. A. Cowan. « Electronic properties of the dissimilatory sulphite reductase from Desulfovibrio vulgaris (Hildenborough) : comparative studies of optical spectra and relative reduction potentials for the [Fe4S4]-sirohaem prosthetic centres ». Biochemical Journal 304, no 2 (1 décembre 1994) : 441–47. http://dx.doi.org/10.1042/bj3040441.

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The dissimilatory sulphite reductase (desulfoviridin) from the sulphate-reducing bacterium Desulfovibrio vulgaris (Hildenborough) displays distinct optical and redox characteristics relative to the haem subunit of Escherichia coli assimilatory sulphite reductase. For high-spin pentaco-ordinate desulfoviridin there is minimal change in the absorbance of the oxidized chromophores both after reduction or after addition of exogenous ligands. A ligand-metal charge-transfer band approximately 702 nm is observed in both the oxidized and one-electron-reduced enzyme. E.p.r. spectroscopy has been used to define the relative reduction potentials for sirohaem and [Fe4S4] centres (delta E0 = Es0-Ec0) as a function of sirohaem axial co-ordination. Typically delta E0 lies in a range from -10 to -50 mV. These results show a correlation with the sigma-donor or pi-acceptor properties of the ligand and stand in sharp contrast with estimates for the E. coli enzyme. The electronic properties of the coupled [Fe4S4]-sirohaem redox centre common to both nitrite- and sulphite-reducing enzymes are apparently strongly dependent on the environment generated by protein side chains.
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Yu, Shuai Qin, et Hong Nan Ye. « A DFT Study of Geometric Structure and Stability of Iron-Silicon Clusters ». Advanced Materials Research 1048 (octobre 2014) : 369–72. http://dx.doi.org/10.4028/www.scientific.net/amr.1048.369.

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Geometric structures of Fe6-xSix(x=1-5) clusters have been systematically studied at the BPW91 level by density-functional theory (DFT). Calculated results show that the Fe atoms of the lowest-energy structures of Fe6-xSix clusters tend to go together, and Si atoms tend to occupy surface site bonding with iron atoms as many as possible. Further, we analyze the stability of the lowest-energy structures of Fe6-xSix clusters, and the corresponding results of the HOMO, LUMO as well as the HOMO-LUMO energy gap show that the Fe5Si and Fe4Si2 clusters have special stability.
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Saak, Wolfgang, et Siegfried Pohl. « lodsubstituierte Eisen-Schwefel-Cluster : Neue Synthesen sowie zur Bildung und Stabilität von Fe2S2I42-, Fe4S4I42– und Fe6S6I62-. Die Kristallstruktur von (Et4N)6(Fe4S4l4)2Fe2S2l4 / Iodine Substituted Iron-Sulfur-Clusters : Novel Syntheses, Formation and Stability of Fe2S2I42-, Fe4S4I42- und Fe6S6I62-. The Crystal Structure of (Et4N)6(Fe4S4l4)2Fe2S2l4 ». Zeitschrift für Naturforschung B 40, no 9 (1 septembre 1985) : 1105–12. http://dx.doi.org/10.1515/znb-1985-0903.

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Fe4S4I42- has been prepared in tetrahydrofuran (THF) solution by the reaction of Fe, S8, I2, and Me3NCH2Ph+TI-, and isolated as black, fairly air-stable crystals of (Me3NCH2Ph)2Fe4S4I4 (1) in nearly quantitative yield. 1 reacts with iron and iodine or with elemental sulfur and Fel2 in CH2Cl2 solution to form Fe6S6I62- which was isolated as black crystals of (Me3NCH2Ph)2Fe6S6I6 (5). In THF solution Fe6S6I62- is converted to Fe4S4I42- which was isolated as Fe(THF)6Fe4S4I4·4 THF (3). Evidence is presented for an equilibrium between Fe2S2I42- and Fe4S4I42-, Fel42- and sulfur when iron, sulfur, iodine and Et4N+I- react (with the required stoichiometry) to form Fe2S2I42- in CH2Cl2 solution. From this solution (Et4N)6(Fe4S4I4)2Fe2S2I4 (6 ) crystallizes as black needles (tetragonal, P42bc, a = 2467.9, b = 1653.8 pm, Z = 4). Crystals of 6 consist of the discrete anions Fe4S4I42- and Fe2S2I42- and Et4N+ cations. The [Fe4S4]2+ core does not exhibit the usually observed core distortion. This clearly demonstrates that additional ligands (THF, CH3CN, iodide ions etc.) strongly reduce the stability of iodine substituted Fe/S clusters (except [Fe4S4]2+ cores!). The biological relevance of the observed rearrangements is discussed.
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Borras-Almenar, J. J., R. Jorge, S. I. Klokishner, E. Coronado, S. M. Ostrovskii, A. V. Palii et B. S. Tsukerblat. « Double exchange in polynuclear mixed-valence clusters. 2. Iron-sulfur proteins [Fe4S4]+ and [Fe4S4]3+ ». Journal of Structural Chemistry 37, no 5 (septembre 1996) : 699–706. http://dx.doi.org/10.1007/bf02437031.

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Banci, L. « The electronic structure of Fe4S4 clusters ». Journal of Inorganic Biochemistry 56, no 1 (octobre 1994) : 52. http://dx.doi.org/10.1016/0162-0134(94)85092-5.

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Noodleman, Louis. « Fe4S4 clusters as small molecule catalysts ». Nature Catalysis 1, no 6 (juin 2018) : 383–84. http://dx.doi.org/10.1038/s41929-018-0099-0.

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Gao, Jiancun, Hongbin Sui, Siyuan Wu, Renyou Zhang, Mengxin Zhang, Bolun Cui et Huilin Chu. « Interaction Study of Oxygen and Iron-Sulfur Clusters Based on the Density Functional Theory ». International Journal of Chemical Engineering 2022 (24 septembre 2022) : 1–9. http://dx.doi.org/10.1155/2022/9812188.

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For the petrochemical industry, the spontaneous burning of iron sulfide compounds has been a major issue. In this study, XRD characterization of samples of iron sulfide compounds with spontaneous combustion tendency revealed that amorphous FeS was the primary constituent of the samples. A molecular simulation was used to build an amorphous FeS cluster model, and the density functional theory was used to examine the adsorption and reactivity characteristics of Fe4S4 clusters with O2. Different adsorption structures are generated by considering different adsorption sites and the electronic characteristics of each adsorption structure are evaluated. The results show that O2 prefers to adsorb around Fe atoms and has repulsion with S atoms, and the adsorption energy is maximum when two O atoms are co-adsorbed around Fe atoms, which is 198.13 kJ/mol. After adsorption charge, oxygen is in the superoxide state. The calculation of the reaction path divides the reaction process into different stages and considers different reaction routes. A thorough evaluation of the energy barriers and reaction energies of the two exothermic reactions leads to the conclusion that reaction path 1 is the optimal reaction path, and the reaction can release a total of 582.76 kJ/mol of heat. According to calculations, dimeric sulfur S2 must absorb a large part amount of energy in order to conduct the oxidation process. However, because S2 is present in the Fe4S4 reaction system, it may start the oxidation reaction by absorbing heat from the system and releasing 470.94 kJ/mol of heat. As a result, we conclude that this spontaneous exothermic reaction is a major cause of iron sulfide compounds spontaneous combustion. The thermal oxidation of the dimeric sulfur S2 generated in the reaction system releases heat that aggregates with the heat from the Fe4S4 cluster’s oxidation reaction system, eventually causing spontaneous combustion as a result of the heat’s continual buildup. In this study, we explore the reason for the extremely easy oxidation and spontaneous burning of iron sulfide compounds from a microscopic perspective to provide a theoretical foundation for the prevention and control of iron sulfide compound spontaneous combustion in the petrochemical sector.
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M�ller, A., et N. H. Schladerbeck. « Einfache aerobe Bildung eines {Fe4S4}2+-Clusterzentrums ». Naturwissenschaften 73, no 11 (novembre 1986) : 669–70. http://dx.doi.org/10.1007/bf00366688.

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Koay, Melissa S, Mikhail L Antonkine, Wolfgang Gärtner et Wolfgang Lubitz. « Modelling Low-Potential [Fe4S4] Clusters in Proteins ». Chemistry & ; Biodiversity 5, no 8 (août 2008) : 1571–87. http://dx.doi.org/10.1002/cbdv.200890145.

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Gebbink, Robertus J. M. Klein, Stephen I. Klink, Martinus C. Feiters et Roeland J. M. Nolte. « Fe4S4 Clusters Functionalized with Molecular Receptor Ligands ». European Journal of Inorganic Chemistry 2000, no 9 (septembre 2000) : 2087–99. http://dx.doi.org/10.1002/1099-0682(200009)2000:9<2087 ::aid-ejic2087>3.0.co;2-n.

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Kambayashi, Hide, Masami Nakamoto, Shie-Ming Peng, Hirotaka Nagao et Koji Tanaka. « Crystal Structure of (Ph4As)2[Fe4S4(SAd)4] and Stabilization of [Fe4S4(SAd)4]−State in Aqueous Media ». Chemistry Letters 21, no 6 (juin 1992) : 919–22. http://dx.doi.org/10.1246/cl.1992.919.

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Bierbach, Ulrich, Wolfgang Saak, Detlev Haase et Siegfried Pohl. « Neutrale und kationische Eisen-Schwefel-Komplexe und -Cluster Synthese und Kristallstrukturen von [Fe(SR)2L2] · PhMe und [Fe4S4(SR)2L2] sowie zur Bildung von [Fe(SR)L3]+, [FeL4]2+, [Fe4S4(SR)L3]+ und [Fe4S4L4]2+ (R = 2,4,6-i-Pr3C6H2 ; L = SC(NMe2)2) / Neutral and Cationic Iron-Sulfur Complexes and Clusters Syntheses and Crystal Structures of [Fe(SR),L2] · PhMe and [Fe4S4(SR)2L2], and on the Formation of [Fe(SR)L3]+, [FeL4]2+, [Fe4S4(SR)L3]+ and [Fe4S4L4]2+ (R = 2,4,6-i-Pr3C6H2 ; L = SC(NMe2)2) ». Zeitschrift für Naturforschung B 46, no 12 (1 décembre 1991) : 1629–34. http://dx.doi.org/10.1515/znb-1991-1208.

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The reaction of [FeI2L2] (1; L = SC(NMe2)2) with KSR (R = 2,4,6-i-Pr3C6H,) yields [Fe(SR)2L2] · PhMe (2).Oxidation of the thiolate ligands of 2 with ((Me2N)2CSSC(NMe2)2)2+ affords the cationic complexes [Fe(SR)L3]+ and [FeL4]2+, which were isolated as tetraphenylborate salts.A mixed ligand neutral iron sulfur cluster [Fe4S4(SR)2L2] (3) has been synthesized by the reaction of 2 with elemental sulfur. 3 is a precursor for cationic clusters which are obtained via the above-mentioned oxidation. The structures of 2 and 3 were determined from single crystal X-ray diffraction data.2 crystallizes in the monoclinic space group C2/c with a = 1807.8(1), b = 1000.6(1), c = 2946.0(2) pm, β = 101.16(1), V = 5227.6 × 106 pm3, Ζ = 4, R = 0.067. The complex exhibits C2-symmetry and a distorted tetrahedral coordination of Fe(II) (S–Fe–S angles between 101.7 and 125.7). The Fe–Sthiourea and Fe–Sthiolate bond lengths were found to be 240.3(2) and 231.5(1) pm, respectively.3: triclinic, P1, a= 1020.2(2), b = 1035.3(2), c = 1402.1(2) pm, α = 73.50(1), β = 70.47(1), γ=84.38(1),V= 1338.2 × 106pm3,Z= 1, R = 0.039.3 shows a slightly compressed Fe4S4 core structure. The Fe– Fe distances range from 269.1 to 278.1 pm. The shortest and longest distances are observed between those Fe atoms which have two thiourea and two thiolate ligands, respectively.
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Gloux, Jocelyne, Pierre Gloux, Bernard Lamotte, Jean-Marie Mouesca et Gerard Rius. « The Different [Fe4S4]3+ and [Fe4S4]+ Species Created by .gamma. Irradiation in Single Crystals of the (Et4N)2[Fe4S4(SBenz)4] Model Compound : Their EPR Description and Their Biological Significance ». Journal of the American Chemical Society 116, no 5 (mars 1994) : 1953–61. http://dx.doi.org/10.1021/ja00084a040.

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Neumann, Anke, Gert Wohlfarth et Gabriele Diekert. « Tetrachloroethene Dehalogenase from Dehalospirillum multivorans : Cloning, Sequencing of the Encoding Genes, and Expression of the pceA Gene in Escherichia coli ». Journal of Bacteriology 180, no 16 (15 août 1998) : 4140–45. http://dx.doi.org/10.1128/jb.180.16.4140-4145.1998.

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ABSTRACT The genes encoding tetrachloroethene reductive dehalogenase, a corrinoid-Fe/S protein, of Dehalospirillum multivorans were cloned and sequenced. The pceA gene is upstream ofpceB and overlaps it by 4 bp. The presence of a ς70-like promoter sequence upstream of pceA and of a ρ-independent terminator downstream of pceB indicated that both genes are cotranscribed. This assumption is supported by reverse transcriptase PCR data. The pceA and pceB genes encode putative 501- and 74-amino-acid proteins, respectively, with calculated molecular masses of 55,887 and 8,354 Da, respectively. Four peptides obtained after trypsin treatment of tetrachloroethene (PCE) dehalogenase were found in the deduced amino acid sequence of pceA. The N-terminal amino acid sequence of the PCE dehalogenase isolated from D. multivorans was found 30 amino acids downstream of the N terminus of the deduced pceA product. The pceAgene contained a nucleotide stretch highly similar to binding motifs for two Fe4S4 clusters or for one Fe4S4 cluster and one Fe3S4 cluster. A consensus sequence for the binding of a corrinoid was not found in pceA. No significant similarities to genes in the databases were detected in sequence comparisons. The pceB gene contained two membrane-spanning helices as indicated by two hydrophobic stretches in the hydropathic plot. Sequence comparisons of pceBrevealed no sequence similarities to genes present in the databases. Only in the presence of pUBS 520 supplying the recombinant bacteria with high levels of the rare Escherichia colitRNA4 Arg was pceA expressed, albeit nonfunctionally, in recombinant E. coli BL21 (DE3).
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Fay, Aaron W., Jared A. Wiig, Chi Chung Lee et Yilin Hu. « Identification and characterization of functional homologs of nitrogenase cofactor biosynthesis protein NifB from methanogens ». Proceedings of the National Academy of Sciences 112, no 48 (16 novembre 2015) : 14829–33. http://dx.doi.org/10.1073/pnas.1510409112.

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Nitrogenase biosynthesis protein NifB catalyzes the radical S-adenosyl-L-methionine (SAM)-dependent insertion of carbide into the M cluster, the cofactor of the molybdenum nitrogenase from Azotobacter vinelandii. Here, we report the identification and characterization of two naturally “truncated” homologs of NifB from Methanosarcina acetivorans (NifBMa) and Methanobacterium thermoautotrophicum (NifBMt), which contain a SAM-binding domain at the N terminus but lack a domain toward the C terminus that shares homology with NifX, an accessory protein in M cluster biosynthesis. NifBMa and NifBMt are monomeric proteins containing a SAM-binding [Fe4S4] cluster (designated the SAM cluster) and a [Fe4S4]-like cluster pair (designated the K cluster) that can be processed into an [Fe8S9] precursor to the M cluster (designated the L cluster). Further, the K clusters in NifBMa and NifBMt can be converted to L clusters upon addition of SAM, which corresponds to their ability to heterologously donate L clusters to the biosynthetic machinery of A. vinelandii for further maturation into the M clusters. Perhaps even more excitingly, NifBMa and NifBMt can catalyze the removal of methyl group from SAM and the abstraction of hydrogen from this methyl group by 5′-deoxyadenosyl radical that initiates the radical-based incorporation of methyl-derived carbide into the M cluster. The successful identification of NifBMa and NifBMt as functional homologs of NifB not only enabled classification of a new subset of radical SAM methyltransferases that specialize in complex metallocluster assembly, but also provided a new tool for further characterization of the distinctive, NifB-catalyzed methyl transfer and conversion to an iron-bound carbide.
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Gloux, J., P. Gloux, H. Hendriks et G. Rius. « EPR study of the [Fe4S4]+ and [Fe4S4]3+ states in .gamma.-irradiated crystals of (Bu4N)2[Fe4S4(SPh)4]. ~g Tensors in relation to the geometry of the 4Fe-4S core ». Journal of the American Chemical Society 109, no 11 (mai 1987) : 3220–24. http://dx.doi.org/10.1021/ja00245a006.

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Evans, David J., Adrian Hills, David L. Hughes, Geoffrey J. Leigh, Andrew Houlton et Jack Silver. « Lattice effects in the Mössbauer spectra of salts of [Fe4S4(SBut)4]2–. Crystal structures of [NMe4]2[Fe4S4(SBut)4]·HSButand [N(n-C5H11)4]2[Fe4S4(SBut)4]·HSBut ». J. Chem. Soc., Dalton Trans., no 9 (1990) : 2735–41. http://dx.doi.org/10.1039/dt9900002735.

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Ye, Mengshan, Niklas B. Thompson, Alexandra C. Brown et Daniel L. M. Suess. « A Synthetic Model of Enzymatic [Fe4S4]–Alkyl Intermediates ». Journal of the American Chemical Society 141, no 34 (2 août 2019) : 13330–35. http://dx.doi.org/10.1021/jacs.9b06975.

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Begum, Ameerunisha, Golam Moula, Moumita Bose et Sabyasachi Sarkar. « Super reduced Fe4S4 cluster of Balch's dithiolene series ». Dalton Transactions 41, no 12 (2012) : 3536. http://dx.doi.org/10.1039/c2dt12184k.

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Evans, David J., et G. Jeffery Leigh. « Serinato-, tyrosinato-, and prolinato-derivatives of Fe4S4 clusters ». Journal of the Chemical Society, Chemical Communications, no 5 (1988) : 395. http://dx.doi.org/10.1039/c39880000395.

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Zhu, Nianyong, Ralf Appelt et Heinrich Vahrenkamp. « Attachment of cyanometal units to the Fe4S4 cluster ». Journal of Organometallic Chemistry 565, no 1-2 (août 1998) : 187–92. http://dx.doi.org/10.1016/s0022-328x(98)00435-5.

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Hoppe, Alessandra, Maria-Eirini Pandelia, Wolfgang Gärtner et Wolfgang Lubitz. « [Fe4S4]- and [Fe3S4]-cluster formation in synthetic peptides ». Biochimica et Biophysica Acta (BBA) - Bioenergetics 1807, no 11 (novembre 2011) : 1414–22. http://dx.doi.org/10.1016/j.bbabio.2011.06.017.

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Noda, Sumio, Shigetsohi Aono et Ichiro Okura. « Photoinduced electron transfer with [Fe4S4(SC6F5)4]2− ». Journal of Molecular Catalysis 50, no 2 (mars 1989) : 119–22. http://dx.doi.org/10.1016/0304-5102(89)85055-2.

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Zhu, Nianyong, Jürgen Pebler et Heinrich Vahrenkamp. « Kombination der Fe4S4- und M-CN-Fe-Redoxfunktionen ». Angewandte Chemie 108, no 8 (18 avril 1996) : 984–85. http://dx.doi.org/10.1002/ange.19961080828.

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Gebbink, Robertus J. M. Klein, Stephen I. Klink, Martinus C. Feiters et Roeland J. M. Nolte. « “Crowned” Fe4S4 Clusters as Electrochemical Metal Ion Sensors ». European Journal of Inorganic Chemistry 2000, no 2 (février 2000) : 253–64. http://dx.doi.org/10.1002/(sici)1099-0682(200002)2000:2<253 ::aid-ejic253>3.0.co;2-m.

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Jordanov, J., E. K. H. Roth, P. H. Fries et L. Noodleman. « Magnetic studies of the high-potential protein model [Fe4S4(S-2,4,6-(iso-Pr)3C6H2)4]- in the [Fe4S4]3+ oxidized state ». Inorganic Chemistry 29, no 21 (octobre 1990) : 4288–92. http://dx.doi.org/10.1021/ic00346a025.

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