Article
Chemistry, Multidisciplinary
Claudia Brocks, Chandan K. Das, Jifu Duan, Shanika Yadav, Ulf-Peter Apfel, Subhasri Ghosh, Eckhard Hofmann, Martin Winkler, Vera Engelbrecht, Lars V. Schaefer, Thomas Happe
Summary: This study proposes a new strategy to improve the O-2 stability of [FeFe]-hydrogenases by blocking the O-2 diffusion pathway and protecting the catalytic cofactor.
Article
Chemistry, Multidisciplinary
Maria Alessandra Martini, Konstantin Bikbaev, Yunjie Pang, Christian Lorent, Charlotte Wiemann, Nina Breuer, Ingo Zebger, Serena DeBeer, Ingrid Span, Ragnar Bjornsson, James A. Birrell, Patricia Rodriguez-Macia
Summary: [FeFe] hydrogenase variants with a mutation in the proton transfer pathway can form two new active site states with a CN- ligand bound to the apical position of [2Fe](H). These states can be generated by either cannibalization from damaged [2Fe](H) subclusters or addition of exogenous CN-. This study provides the first detailed characterization of the interaction between exogenous CN- and [FeFe] hydrogenases.
Review
Microbiology
Simone Morra
Summary: FeFe-hydrogenases are complex metalloenzymes that play a key role in microbial energy metabolism. They use protons from water as terminal electron acceptors to dissipate excess reducing equivalents and produce hydrogen. FeFe-hydrogenases also have additional physiological functions, such as H-2 uptake, H-2 sensing, and CO2 fixation. Recent advancements in identifying and characterising novel FeFe-hydrogenases have expanded our understanding of their multiple roles and mechanisms.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Shuanglin He, Fang Huang, Qianqian Wu, Ping Zhang, Ying Xiong, Jie Yang, Rong Zhang, Fang Wang, Lin Chen, T. Leo Liu, Fei Li
Summary: A rare mononuclear manganese complex was reported as a mimic of [FeFe]-hydrogenase, successfully mimicking the functions of its active site by utilizing two consecutive MS-CPET processes to achieve low overpotential in electrochemical hydrogen production.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Andreas Rutz, Chandan K. Das, Andrea Fasano, Jan Jaenecke, Shanika Yadav, Ulf-Peter Apfel, Vera Engelbrecht, Vincent Fourmond, Christophe Leger, Lars Schaefer, Thomas Happe
Summary: The active site of [FeFe]-hydrogenases degrades upon contact with oxygen, but the protein structure of a certain hydrogenase (CbA5H) allows its active site to be protected, reducing degradation caused by oxygen. By modifying the surface residue, the hydrogenase's resistance to oxygen can be increased.
Article
Biochemistry & Molecular Biology
Andrea Mele, Federica Arrigoni, Catherine Elleouet, Francois Y. Petillon, Philippe Schollhammer, Giuseppe Zampella
Summary: This study investigates the behavior of triazolylidene ligands on the active site of [FeFe]-hydrogenases and reveals that these carbenes do not possess redox properties. Additionally, comparing different structures of carbenes shows that the substitution of groups in the triazole heterocycle affects their spectroscopic characteristics. Although one carbene exhibits weak catalytic performance in proton reduction, DFT analysis demonstrates that the protonation process is favored by S-protonation but hindered by the stable diprotonated intermediate, which explains the low efficiency in the Hydrogen Evolution Reaction. These findings are of significance for further research and applications of metal carbenes in redox processes.
Review
Chemistry, Physical
Matteo Sensi, Carole Baffert, Vincent Fourmond, Luca de Gioia, Luca Bertini, Christophe Leger
Summary: This review presents evidence that hydrogenases are photosensitive, focusing on FeFe hydrogenases with their active site called the H-cluster, consisting of a [4Fe4S] cluster and a diiron site. It discusses the effects of UV-visible light irradiation on the enzyme and warns about FeFe hydrogenase photoinhibition when using them for artificial photosynthesis.
SUSTAINABLE ENERGY & FUELS
(2021)
Article
Chemistry, Multidisciplinary
Federica Arrigoni, Luca De Gioia, Catherine Elleouet, Francois Y. Petillon, Philippe Schollhammer, Jean Talarmin, Giuseppe Zampella
Summary: In this study, three hexacarbonyl diiron dithiolate complexes with different substituted bridgeheads were investigated using cyclic voltammetry under the same experimental conditions. DFT calculations were conducted to explain the reduction mechanism of these compounds. The three complexes undergo a two-electron transfer, and the mechanism depends on the bulkiness of the dithiolate bridge, which results in different timing of structural changes compared to the redox steps. The introduction of a bulky group in the dithiolate linker affects the reduction potentials and the kinetics of electron transfer.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Georgia R. F. Orton, Shishir Ghosh, Lucy Alker, Jagodish C. Sarker, David Pugh, Michael G. Richmond, Frantisek Hartl, Graeme Hogarth
Summary: In this study, FeFe biomimics containing redox-active ferrocenyl diphosphine were prepared and their ability to reduce protons and oxidize H-2 was investigated. The complexes exhibited different chemical behavior in oxidation reactions in different solvents, providing valuable insights for studying their catalytic performances.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Xiao-Li Gu, Bo Jin, Xiao Tan, Pei-Hua Zhao
Summary: A new aminophosphine-substituted diiron oxadithiolate complex and its reference analogue were synthesized and characterized, with investigations on their protonation and electrochemistry properties in the presence of strong and weak acids. The study revealed that the complexes exhibited reactivity towards the strong acid but not the weak acid, and they showed potential as active biomimetic electrocatalysts for proton reduction to hydrogen.
INORGANIC CHEMISTRY COMMUNICATIONS
(2021)
Article
Chemistry, Applied
Xu-Feng Liu, Zhong-Yi Ma, Bo Jin, Dong Wang, Pei-Hua Zhao
Summary: In this study, a new series of azadithiolato-bridged diiron complexes supported by tertiary phosphines were prepared and characterized as potential active site models of [FeFe]-hydrogenases. The introduction of different substituents on the phosphine ligands allows for adjustment of the electron density of the diiron center, which in turn affects the structure and electrochemical performance of these complexes.
APPLIED ORGANOMETALLIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Shu-Fen Bai, Jun-Wei Ma, Ya-Nan Guo, Xiu-Mei Du, Yan-Lan Wang, Qian-Li Li, Shuang Lu
Summary: Researchers successfully prepared four types of aminophosphine substituted Fe/E (E = S, Se) carbonyls related to [FeFe]-hydrogenases. These compounds have interesting structures and can be used for electrocatalytic hydrogen production.
JOURNAL OF MOLECULAR STRUCTURE
(2023)
Article
Chemistry, Inorganic & Nuclear
Francesca Realini, Catherine Elleouet, Francois Y. Petillon, Philippe Schollhammer
Summary: Novel carbonyl dithiolato diiron complexes related to the active site of [FeFe]-hydrogenases have been synthesized and characterized. Their fluxionality in solution and bridge motion were studied using NMR experiments. Preliminary results on protonation and electrochemical properties were reported.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
Review
Chemistry, Multidisciplinary
Adrien Pagnier, Batuhan Balci, Eric M. Shepard, William E. Broderick, Joan B. Broderick
Summary: The assembly and installation of the [FeFe]-hydrogenase H-cluster is not fully understood, but in vitro approaches using semisynthetic and enzyme-based methods have provided new insights into the maturation process. These approaches have shed light on the roles of individual maturation enzymes, the nature of H-cluster assembly intermediates, the molecular precursors of H-cluster ligands, and the sequence of steps involved in [FeFe]-hydrogenase maturation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Fanjun Zhang, Toby J. Woods, Lingyang Zhu, Thomas B. Rauchfuss
Summary: The inhibition mechanism of [FeFe]-hydrogenases by formaldehyde involves the covalent linking of Fe and the amine cofactor via CH2 donation from formaldehyde, forming a versatile electrophilic Fe-alkyl. Reactions with various reagents demonstrate the electrophilic nature of the Fe-CH2N bond in the resulting complexes, allowing for diverse chemical transformations.
Article
Chemistry, Physical
Casey Van Stappen, Bardi Benediktsson, Atanu Rana, Aleksandr Chumakov, Yoshitaka Yoda, Dimitrios Bessas, Laure Decamps, Ragnar Bjornsson, Serena DeBeer
Summary: In this study, the electronic structure and dynamics of the catalytic components of three unique M N(2)ase enzymes (M = Mo, V, Fe) were investigated using synchrotron-based Fe-57 nuclear resonance vibrational spectroscopy and DFT-based QM/MM calculations. The results provide vibrational mode assignments for the FeMco clusters and demonstrate the sensitivity of the calculated partial vibrational density of states to the geometric and electronic structures of these clusters. The study also discusses the challenges faced when using NRVS to investigate large, multi-component metalloenzymatic systems and outlines the scope and limitations of current theory in reproducing complex spectra.
FARADAY DISCUSSIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Sivathmeehan Yogendra, Daniel W. N. Wilson, Anselm W. Hahn, Thomas Weyhermuller, Casey Van Stappen, Patrick Holland, Serena DeBeer
Summary: This article reports a series of di-iron clusters supported by dianionic yldiide ligands, in which the Fe sites are bridged by two mu 2-C atoms and four pendant S donors. The mixed-valence cluster displays two peaks in the Moessbauer spectra, indicating slow electron transfer between the two sites.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Carli B. Kovel, Jonathan M. Darmon, S. Chantal E. Stieber, Gisselle Pombar, Tyler P. Pabst, Bastian Theis, Zoe R. Turner, Okten Ungor, Michael Shatruk, Serena DeBeer, Paul J. Chirik
Summary: This article describes the application of bimolecular reductive elimination in the activation of iron catalysts for alkene-diene cycloaddition. The synthesis, characterization, electronic structure determination, and solution stability of a family of pyridine(diimine) iron methyl complexes with diverse steric properties and electronic ground states were key to this approach. These complexes exhibited distorted molecular structures and S = 3/2 ground states. The addition of butadiene to these complexes induced ethane formation and activated the iron catalysts for the cycloaddition reaction.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Weiqing Mao, Zihan Zhang, Dominik Fehn, Sergio A. V. Jannuzzi, Frank W. Heinemann, Andreas Scheurer, Maurice van Gastel, Serena DeBeer, Dominik Munz, Karsten Meyer
Summary: This study describes the synthesis, characterization, and reactivity of a series of cobalt terminal imido complexes supported by an N-anchored tripodal tris(carbene) chelate. The complexes were fully characterized using various spectroscopic and crystallographic techniques. Quantum chemical calculations provided insight into the electronic structures of the compounds. The findings highlight the reactivity of these cobalt imido complexes, including their ability to undergo intramolecular C-H bond amination and nucleophilic addition reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yuyan Zhang, Sami El Sayed, Liqun Kang, Matthew Sanger, Thomas Wiegand, Philip G. Jessop, Serena Debeer, Alexis Bordet, Walter Leitner
Summary: Ruthenium nanoparticles immobilized on an amine-functionalized polymer-grafted silica support can selectively catalyze the hydrogenation of bicyclic heteroaromatics. The addition of CO2 to the hydrogen gas phase can effectively shut down the arene hydrogenation reaction while maintaining activity for heteroaromatic hydrogenation. This selectivity switch is achieved through the catalytic generation of ammonium formate species on the material's surface by hydrogenation of CO2. By altering the composition of the feed gas, a variety of benzofuran and quinoline derivatives can be selectively hydrogenated to fully or partially saturated products using a single catalyst.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Aleksandra Wandzilak, Katarzyna Grubel, Kazimer L. Skubi, Sean F. Mcwilliams, Dimitrios Bessas, Atanu Rana, Stefan Hugenbruch, Abhishek Dey, Patrick L. Holland, Serena Debeer
Summary: This study successfully elucidated the characteristics and mechanism of the intermediate species during the cleavage of the strong triple bond of N2 by Diketiminate-supported iron complexes, using a range of spectroscopic techniques and computational models.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Alexandre Genoux, Magnus Pauly, Conor L. Rooney, Chungseok Choi, Bo Shang, Scott McGuigan, Majed S. Fataftah, Yves Kayser, Simon C. B. Suhr, Serena Debeer, Hailiang Wang, Paul A. Maggard, Patrick L. Holland
Summary: Carbon nitride materials with stoichiometric iron sites having the same environment were synthesized and characterized. The material showed tetrahedral high-spin iron(II) sites throughout and exhibited excellent electrocatalytic activity for nitrate reduction to ammonia.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yang Liu, Sayanti Chatterjee, George E. Cutsail III, Sergey Peredkov, Sandeep K. Gupta, Sebastian Dechert, Serena DeBeer, Franc Meyer
Summary: This study reports the synthesis and characterization of [Cu-4(& mu;(4)-S)](n+) (n = 2, 2; n = 3, 3) clusters, which mimic the two active states of the Cu-Z* site during enzymatic N2O reduction. The structural and electronic properties of these clusters are elucidated using multiple methods. Preliminary reactivity studies demonstrate the nucleophilic character of the central & mu;(4)-S in the fully reduced 0-hole state.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Nipa Chongdar, Patricia Rodriguez-Macia, Edward J. Reijerse, Wolfgang Lubitz, Hideaki Ogata, James A. Birrell
Summary: This study investigates the influence of the protein environment on the catalytic, spectroscopic, and redox properties of [FeFe] hydrogenases. Mutations at the non-conserved serine 267 site resulted in a significant decrease in activity and a lower redox potential for the [4Fe-4S] subcluster. These findings highlight the important role of the secondary coordination sphere in tuning the catalytic properties of [FeFe] hydrogenases.
Article
Chemistry, Multidisciplinary
Maria Alessandra Martini, Konstantin Bikbaev, Yunjie Pang, Christian Lorent, Charlotte Wiemann, Nina Breuer, Ingo Zebger, Serena DeBeer, Ingrid Span, Ragnar Bjornsson, James A. Birrell, Patricia Rodriguez-Macia
Summary: [FeFe] hydrogenase variants with a mutation in the proton transfer pathway can form two new active site states with a CN- ligand bound to the apical position of [2Fe](H). These states can be generated by either cannibalization from damaged [2Fe](H) subclusters or addition of exogenous CN-. This study provides the first detailed characterization of the interaction between exogenous CN- and [FeFe] hydrogenases.
Review
Chemistry, Physical
Andreas Erbe, Marc Frederic Tesch, Olaf Ruediger, Bernhard Kaiser, Serena DeBeer, Martin Rabe
Summary: Inspired by photosystem II, Mn oxide based electrocatalysts have been studied as catalysts for the electrochemical oxygen evolution reaction (OER). However, there are fundamental differences between biological OER catalyzed by CaMn4Ox and the requirements for an electrocatalyst in industrial applications. In this paper, the challenges and recent insights gained from in situ and operando methods, such as vibrational spectroscopy, absorption techniques, and operando X-ray spectroelectrochemistry, are discussed. Despite technical and Mn specific challenges, three key features, including structural disorder, Mn oxidation states between III and IV, and the appearance of layered birnessite phases, are common to most systems with significant OER activity.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Rhiannon M. Evans, Stephen E. Beaton, Patricia Rodriguez Macia, Yunjie Pang, Kin Long Wong, Leonie Kertess, William K. Myers, Ragnar Bjornsson, Philip A. Ash, Kylie A. Vincent, Stephen B. Carr, Fraser A. Armstrong
Summary: A variant of hydrogenase-2 from E. coli with a mutated arginine residue at its active site forms a tightly-bound diatomic ligand. This ligand is stabilized by hydrogen bonding and removal only occurs after reduction with H-2 and reduced methyl viologen. The R479K variant shows decreased rates in hydrogen oxidation and evolution compared to the native enzyme. Importance rating: 7/10.
Article
Chemistry, Multidisciplinary
Carli B. Kovel, Jonathan M. Darmon, S. Chantal E. Stieber, Gisselle Pombar, Tyler P. Pabst, Bastian Theis, Zoe R. Turner, Okten Ungor, Michael Shatruk, Serena DeBeer, Paul J. Chirik
Summary: This study describes the application of bimolecular reductive elimination to activate iron catalysts for alkene-diene cycloaddition. The synthesis, characterization, electronic structure determination, and solution stability of a family of pyridine(diimine) iron methyl complexes with different steric properties and electronic ground states are crucial to this approach. The investigations elucidate the electronic and steric features of the iron complexes that enable the unusual reductive elimination and precatalyst activation pathway.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Maria Chrysina, Maria Drosou, Rebeca G. Castillo, Michael Reus, Frank Neese, Vera Krewald, Dimitrios A. Pantazis, Serena Debeer
Summary: This research investigates the water splitting enzyme in Photosystem II using high-energy resolution fluorescence detected X-ray absorption spectroscopy. By combining quantum chemical calculations and experimental data analysis, the geometric and electronic structures of different catalytic intermediates are determined, ruling out the presence of peroxo or oxyl radicals.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
