Article
Biochemistry & Molecular Biology
Mi-jie Gao, Ning-hua Cui, Xia 'nan Liu, Xue-bin Wang
Summary: This study reveals specific patterns of bioenergetic and metabolomic alterations in T2DM patients who suffer from LST, and establishes the deficiency of complex I-derived NAD+ as a potential pathogenic mechanism in platelet abnormalities.
Article
Biotechnology & Applied Microbiology
Ke Jiang, Ruoxuan Bai, Ting Gao, Ping Lu, Jingya Zhang, Shuting Zhang, Fangxu Xu, Shenghou Wang, Hongxin Zhao
Summary: In this study, the researchers altered the activity of Complex I by knocking out nuoE, nuoF, and nuoG genes and overexpressing the maeA gene to increase the production of hydrogen. The optimized strain IAM1183-EFG/M showed a 65% increase in hydrogen production compared to the original strain, with significant changes in metabolite content. In a bioreactor, the scale-up IAM1183-EFG/M strain achieved a total hydrogen production of 4.76 L after 44 hours of fermentation, an 18% increase compared to the starting strain. This study provides a new direction for microbial hydrogen production through combinational modification of multiple genes.
MICROBIAL CELL FACTORIES
(2023)
Article
Chemistry, Physical
Denise Lovison, Tobias Berghausen, Sophie R. Thomas, Jonathan Robson, Markus Drees, Christian Jandl, Alexander Poethig, Patrick Mollik, Dominik P. Halter, Walter Baratta, Angela Casini
Summary: In this study, water-soluble organometallic Ru(II) complexes were synthesized and found to act as anticancer agents by catalyzing transfer hydrogenation reactions with biomolecules. The structure-activity relationship and reaction mechanism were investigated, and the compounds were also tested for their anticancer activity in vitro.
Article
Chemistry, Inorganic & Nuclear
Dmitri Gelman, Ilya Kisets, Sofiya Zabelinskaya
Summary: The synthesis and catalytic studies of a prototypical coordinatively rigid carbometalated half-sandwich Ru(II) complex with a rigid polyaromatic tether were described. Despite its coordinatively and electronically saturated nature, the complex demonstrated the ability to activate and transfer hydrogen to polar and nonpolar double bonds. The catalytic activity was benchmarked in the Ru-catalyzed chemoselective hydrogenation of alpha,beta-unsaturated ketones, with initial mechanistic studies suggesting an inner-sphere mechanism via dihydride intermediates.
Article
Chemistry, Inorganic & Nuclear
Joseph M. Mwansa, Matthew J. Stirling, Gemma Sweeney, Jiri Hanusek, Jiri Vana, Michael Page
Summary: A novel dimeric iodo-iridium(iii) complex with an amide moiety within the tetramethylcyclopentadiene ring has been synthesized and characterized. The presence of restricted rotation in the 2-substituted isomer leads to the existence of two distinguishable conformers. The relative acidities of Cp*CONMe2 and Cp* have been compared, and the study also focuses on the decrease in enantiomeric excess during the reduction reaction.
DALTON TRANSACTIONS
(2022)
Review
Chemistry, Inorganic & Nuclear
Tingting Liu, Liandi Wang, Kaikai Wu, Qingfu Wang, Zhengkun Yu
Summary: This article provides a summary of the synthesis and organic synthetic applications of various pincer-type ruthenium(II) complexes. These complexes showed high catalytic activities in transfer hydrogenation of ketones, C-C bond formation from alcohols and ketones, and dehydrogenation reactions. The catalytically active intermediates for these transformations were identified as RuH complexes. The review covers mononuclear ruthenium(II) pincer complexes for (asymmetric) transfer hydrogenation of ketones, multinuclear ruthenium(II) complexes for transfer hydrogenation of ketones, and mononuclear ruthenium(II) complexes for other reactions such as Oppenauer-type oxidation, beta-alkylation of secondary alcohols, synthesis of multisubstituted heterocycles, and acceptorless dehydrogenation of N-heterocycles and secondary alcohols.
INORGANICA CHIMICA ACTA
(2023)
Article
Chemistry, Physical
Qiongyao Chen, Chaoren Shen, Gangli Zhu, Xuehua Zhang, Chun-Lin Lv, Bo Zeng, Sen Wang, Junfen Li, Weibin Fan, Lin He
Summary: This study reveals the role of LiCl in regulating the CO2 hydrogenation pathway with Shvo's complex, demonstrating their collaboration can selectively produce CO from CO2 and efficiently promote this conversion reaction.
Article
Chemistry, Multidisciplinary
Kunlu Liu, Min Wang, Yubo Zhou, Hongxiang Wang, Yudong Liu, Lu Han, Weiwei Han
Summary: The phosphite dehydrogenase (Pdh) catalyzes the oxidation of phosphite to phosphate with the formation of NADH. Different cofactors binding to Pdh, including a smaller-sized NAD analogue nicotinamide cytosine dinucleotide (NCD), can lead to changes in cofactor-binding pockets and secondary structures. These findings can provide a basis for further studies on the Pdh family.
Article
Biophysics
Shanmughan Shamjith, Manu M. Joseph, Vishnu Priya Murali, Geetha S. Remya, Jyothi B. Nair, Cherumuttathu H. Suresh, Kaustabh Kumar Maiti
Summary: In this study, a quinoline-appended iridium complex was developed as a molecular probe for evaluating the endogenous NADH status using fluorescence and surface-enhanced Raman spectroscopy (SERS) techniques. The activated probe showed luminescence (turn-ON) and SERS (turn-OFF) switching phenomenon upon NADH-triggered activation. Additionally, the molecular probe was also demonstrated to function as a photosensitizer for generating singlet oxygen, which could be applied in multiphase photodynamic therapy.
BIOSENSORS & BIOELECTRONICS
(2022)
Article
Chemistry, Inorganic & Nuclear
Mustafa Keles, Mustafa Kemal Yilmaz, Simay Ince, Hulya Keles, Hakan Unver
Summary: Chiral P,N,O type imino- and aminophosphine ligands with various substituents were synthesized and tested for their catalytic performance in asymmetric transfer hydrogenation reactions. The isopropyl-substituted chiral aminophosphine ligand in combination with [Ru(cod)Cl-2] was found to be the most efficient catalyst system for the conversion of aromatic ketones with high enantioselectivity.
INORGANICA CHIMICA ACTA
(2021)
Article
Electrochemistry
Taiki Makizuka, Keisei Sowa, Shiori Katayama, Yuki Kitazumi, Hiroya Yurimoto, Yasuyoshi Sakai, Osamu Shirai
Summary: The translation introduces the significance of nicotinamide adenine dinucleotide redox couple (NAD(+)/NADH) in the catabolism of organisms and mentions the coupling of NAD-dependent enzymatic reactions and NAD+/NADH regenerating systems for biomimetics-associated applications. The article describes a method of constructing a homologous expression system to study the FoDH1 enzyme and its application in a regenerating system.
ELECTROCHIMICA ACTA
(2023)
Article
Oncology
Wei Sun, Yongxiang Zou, Zheng Cai, Jinxiang Huang, Xinjie Hong, Qiang Liang, Weilin Jin
Summary: NNMT is found to be overexpressed in glioma and is associated with poor prognosis. Knockdown of NNMT reduces the volume of glioma and the viability of glioma cells. Overexpression of NNMT epigenetically silences GAP43 and inhibits tumor growth and induces apoptosis through the SIRT1 signaling pathway.
Article
Chemistry, Multidisciplinary
Hideki Ohtsu, Mikio Takaoka, Yosuke Tezuka, Kiyoshi Tsuge, Koji Tanaka
Summary: The study discovered an NAD(+)-type metal complex with oxidizing ability to convert alcohols to aldehydes and ketones, and successfully synthesized a novel zinc(II) complex with a C-C coupling ligand. Kinetic analysis based on absorption spectroscopic measurements revealed that the reaction proceeds through electron transfer followed by proton transfer mechanism.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Veronica Caballero, Rafael Estevez, Diego Luna, Felipa M. Bautista, Antonio A. Romero, Laura Aguado-Deblas, Jesus Hidalgo-Carrillo, Isabel Romero
Summary: In this study, two ruthenium(II) complexes were successfully immobilized on AlPO4-sepiolite, showing good catalytic activity and high enantioselectivity in liquid-phase hydrogenation reactions. The catalyst [(RuCl)Cl(bpea)(DPPE)](BF4)2 exhibited the highest Turn Over Number (TON), while [(RuCl)Cl(bpea){(S)(-)(BINAP)}](BF4) 1 demonstrated better reusability. Additionally, insights into the hydrogenation mechanisms of α,β-unsaturated carbonyl compounds over ruthenium catalysts were obtained.
Article
Chemistry, Multidisciplinary
Jessica Gross, Christoph van Wuellen
Summary: Density functional calculations were used to study the Ru-catalyzed transfer hydrogenation of acetophenone to 1-phenylethanol using isopropanol as the reducing agent. The study revealed that both chloride and triphenylphosphine ligands can initiate the catalytic cycle efficiently, with triphenylphosphine being preferred. Proton transfer within the Ru coordination sphere plays a crucial role in the formation of the product, while product release and catalyst regeneration occur through the dissociation of the neutral product alcohol. The transition state involving beta-hydride transfer from a coordinated isopropanolate anion to ruthenium has the highest Gibbs energy.
ISRAEL JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Takashi Nakazono, Tohru Wada
Summary: The doubly N-confused hexaphyrin dinuclear cobalt complex (Co2DNCH) was shown to be an efficient water oxidation catalyst, outperforming the mononuclear cobalt porphyrin. Utilizing [Ru-II(bpy)(3)](2+) as a photosensitizer and S2O82- as a sacrificial electron acceptor, O-2 was produced with a high turnover number, turnover frequency, and quantum yield.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Laura Rotundo, David C. Grills, Roberto Gobetto, Emanuele Priola, Carlo Nervi, Dmitry E. Polyansky, Etsuko Fujita
Summary: The influence of phenyl, phenol, aniline, amino, and CF substituents of the 2,2'-bipyridine ligand on the photochemical CO2 reduction in dimethylacetamide was examined. The presence of Ph-NH2 moiety was found to enhance both electrochemical and photochemical activity, leading to higher turnover numbers for CO production. The complexes with Ph-OH group in the second coordination sphere also showed promising activity in photochemical CO2 reduction, despite the formation of a stable 6-coordinate intermediate under electrochemical conditions.
Article
Chemistry, Physical
Brian N. DiMarco, Dmitry E. Polyansky, David C. Grills, Ping Wang, Yutaka Kuwahara, Xuan Zhao, Etsuko Fujita
Summary: In this study, the catalytic performance of a series of Co hydrogen evolution catalysts were analyzed by combining electrochemical and transient pulse radiolysis studies. The key factor determining the activity for hydrogen evolution was found to be the hydricity of the [Co-II-H](+) intermediate.
Article
Chemistry, Inorganic & Nuclear
Hiroaki Arima, Misato Wada, Takashi Nakazono, Tohru Wada
Summary: The study focused on investigating chemical and electrochemical 4e(-)-ORR catalyzed by different complexes. Among them, complex 1 showed the highest initial turnover frequency and selectivity for 4e(-)-ORR. Detailed kinetic analyses revealed common rate-determining steps in catalytic cycles of the complexes studied. Through various analyses and reactions, the face-to-face structure of complex 1 with a slightly flexible xanthene was found to be advantageous in enhancing the reaction rate and selectivity for 4e(-)-ORR.
INORGANIC CHEMISTRY
(2021)
Editorial Material
Chemistry, Physical
Laura Rotundo, David C. Grills, Roberto Gobetto, Emanuele Priola, Carlo Nervi, Dmitry E. Polyansky, Etsuko Fujita
Review
Chemistry, Multidisciplinary
Etsuko Fujita, David C. Grills, Gerald F. Manbeck, Dmitry E. Polyansky
Summary: The conversion of carbon dioxide to fuels and chemicals is a promising strategy for renewable energy storage. Molecular catalysts, particularly coordination complexes of transition metals, play a crucial role in the photo- and electrochemical reduction of CO2. The interactions between catalytic intermediates and promoting factors, such as acids and solvents, have a significant impact on the efficiency of catalysis. Mechanistic studies are essential for the design and improvement of efficient catalysts.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Article
Chemistry, Physical
Dmitry E. Polyansky, David C. Grills, Mehmed Z. Ertem, Ken T. Ngo, Etsuko Fujita
Summary: The use of bimetallic catalysts in CO2 reduction can significantly enhance efficiency and reduce overpotential. Experimental and theoretical studies have confirmed the key role of bimetallic reactivity in the reduction of CO2 to CO, revealing the formation of a bimetallic intermediate and the assistance of a coordinating species.
Article
Chemistry, Multidisciplinary
Hiroaki Arima, Takashi Nakazono, Tohru Wada
Summary: This study presents a highly active 4e(-)-ORR catalyst and demonstrates its reactivity under low acid concentration conditions. The research also reveals the reaction mechanism of the catalyst and its interaction with the oxide.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2022)
Article
Chemistry, Inorganic & Nuclear
Laura Rotundo, Shahbaz Ahmad, Chiara Cappuccino, Dmitry E. Polyansky, Mehmed Z. Ertem, Gerald F. Manbeck
Summary: A dicationic Re bipyridine-type complex has been synthesized and studied for its electrochemical behavior under Ar and CO2. The presence of tetra-alkylammonium cations shifts the electrocatalytic potential for CO2 reduction. Cyclic voltammetry, infrared spectroelectrochemistry, and theoretical calculations were used to analyze the electrochemical mechanisms in different solvents and in the presence of weak acids.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Samuel R. Bottum, Taylor S. Teitsworth, Qi Han, Andre D. Orr, Jin-Sung Park, Xiaofan Jia, Chiara Cappuccino, Bobby H. Layne, Nilay Hazari, Javier J. Concepcion, Carrie L. Donley, Dmitry E. Polyansky, Matthew R. Lockett, James F. Cahoon, David C. Grills
Summary: In situ mid-infrared spectroscopy is a powerful technique for understanding the mechanism of CO2 reduction catalysts, while hybrid photoelectrodes, composed of a semiconductor and a molecular catalyst, are promising for sunlight-driven catalysis. We developed a new strategy using ATR-IR spectroscopy coupled with electrochemistry to characterize catalysts directly integrated with a semiconductor surface under applied potential. This technique allows for the investigation of redox processes associated with CO2 reduction catalysts on Si electrode surfaces with high sensitivity.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Multidisciplinary Sciences
Wade C. Henke, Yun Peng, Alex A. Meier, Etsuko Fujita, David C. Grills, Dmitry E. Polyansky, James D. Blakemore
Summary: Protonation reactions of organometallic complexes often generate reactive metal hydrides. However, some organometallic species with Cp* ligands have been found to undergo ligand-centered protonation, leading to the generation of complexes with Cp*H ligands. This study investigates the kinetics and atomistic details of the protonation steps using time-resolved pulse radiolysis and stopped-flow spectroscopy. The results reveal the formation of an elusive hydride complex, Cp*Rh(H)(bpy), via the initial protonation, which further undergoes tautomerization to form Cp*H Rh(bpy). The spectroscopic monitoring of the reaction also shows that both the hydride and Cp*H complex can participate in further reactivity. The mechanistic roles of these intermediates provide insights for the design of catalytic systems using non-innocent cyclopentadienyl-type ligands.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Physical
Dmitry E. Polyansky, Gerald F. Manbeck, Mehmed Z. Ertem
Summary: The formal reduction potentials of highly oxidizing and short-lived radical cations of substituted biphenyls generated in 1,2-dichloroethane (DCE) were measured using a redox equilibrium ladder method. The effect of halide ion-radical interactions on the reduction potentials of biphenyls was investigated, and it was found that the measured potentials saturated at high Hammett sigma values, indicating the influence of ion-pairing and hemicolligation interactions. This study provides a convenient way to manipulate the energetics of electron transfer involving organic redox species.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Takashi Nakazono, Nagisa Amino, Risa Matsuda, Daichi Sugawara, Tohru Wada
Summary: We demonstrated the high catalytic activity of a water-soluble cobalt phthalocyanine complex for visible light-driven photochemical water oxidation and investigated its reaction mechanism using electrochemical and spectroscopic measurements.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Soichi Takasugi, Yugo Miseki, Yoshinari Konishi, Kotaro Sasaki, Etsuko Fujita, Kazuhiro Sayama
Summary: Efficient H2O2 production has been achieved on a carbon cathode modified with various metal salts and an oxide photoanode, with high current density and faradaic efficiency. A simple photoelectrochemical system demonstrated the production of H2O2 from both electrodes without an external bias, with a high total apparent faradaic efficiency and production rate. The solar-to-chemical energy conversion efficiency for H2O2 production without external bias was approximately 1.75%.
