Article
Chemistry, Applied
M. K. Pradhan, S. Dash
Summary: Sm3+ activated inorganic orthophosphate CsMgPO4 (CSMP) phosphors were prepared and studied for their structural, morphological, optical, and photoluminescence properties. The phosphors emitted orange to red light under suitable excitation, showed good thermal stability, and can be used for phosphor-converted white LEDs.
JOURNAL OF RARE EARTHS
(2022)
Article
Spectroscopy
Muhammad Naeem Ashraf, Muhammad Irfan Majeed, Haq Nawaz, Muhammad Adnan Iqbal, Javed Iqbal, Nida Iqbal, Ahmad Hasan, Nosheen Rashid, Muhammad Abubakar, Muhammad Zaman Nawaz, Kashif Shahzad, Muhammad Zeeshan Haider
Summary: In this study, Raman spectroscopy was used to analyze and characterize two salts and their corresponding selenium compounds. The formation of covalent bonds between Se atom and carbon atom of carbene compounds was confirmed through the observation of differences in Raman spectral data. The Raman spectral features provided detailed information about bond formation, chemical and structural differences between salts and compounds. Principal component analysis was found helpful for differentiating each salt from its respective compound.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Chemistry, Inorganic & Nuclear
Hadi Kargar, Mehdi Fallah-Mehrjardi, Reza Behjatmanesh-Ardakani, Mehrnaz Bahadori, Majid Moghadam, Muhammad Ashfaq, Khurram Shahzad Munawar, Muhammad Nawaz Tahir
Summary: A novel palladium(II) Schiff base complex was synthesized by treating an unsymmetrical tetradentate Schiff base ligand with Pd(OAc)2 salt. The complex was characterized using various spectroscopic methods and its crystal structure was examined using single crystal X-ray diffraction. The study revealed that the palladium ion in the complex is tetra-coordinated and exhibits excellent efficiency in Suzuki-Miyaura cross-coupling reactions.
INORGANIC CHEMISTRY COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Anja Bec, Robert Vianello, Marijana Hranjec
Summary: We report multifunctional D-π-A molecular systems with a pH-sensitive donor unit and electron accepting substituents. Three types of derivatives, including acrylonitrile, Schiff base, and iminocoumarin derived benzimidazoles, were synthesized and their photophysical characterization was carried out. The results indicate that these molecules exhibit pH sensing potentials in a broad range of applications.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
M. Frassek, A. Arjun, P. G. Bolhuis
Summary: The paper proposes the use of an extended autoencoder to automate dimensionality reduction in molecular simulation, effectively extracting the underlying mechanism of a reaction, making reliable predictions about the committor of a given configuration, and potentially generating new paths representative for a reaction.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Biochemistry & Molecular Biology
Fenghua Wang, Zehua Xu, Chen Wang, Zehui Guo, Zhaoting Yuan, Hongwei Kang, Jingwen Li, Fuping Lu, Yihan Liu
Summary: In this study, a tyrosinase from Bacillus aryabhattai was functionally expressed and characterized. The recombinant enzyme showed good catalytic activity over a wide range of temperatures and pH levels, and also exhibited high tolerance to salinity and chloride. Additionally, it demonstrated efficient decolorization of various industrial dyes under different conditions, indicating its potential for food industrial applications.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)
Article
Biochemistry & Molecular Biology
Aida Iraji, Negar Sheikhi, Mahshid Attarroshan, Gholam Reaz Sharifi Ardani, Maryam Kabiri, Ali Naghibi Bafghi, Farzad Kobarfard, Zahra Rezaei, Mehdi Khoshneviszadeh, Alireza Foroumadi, Seyedeh Sara Mirfazli
Summary: In this study, 25 indole-carbohydrazide derivatives were synthesized and their structures were confirmed using spectroscopic techniques. These derivatives exhibited inhibitory activity against tyrosinase, with compounds 4f, 8f, and 19e being the most active. The docking study revealed the critical interactions of these potent inhibitors with the active site of the enzyme. Additionally, the derivatives showed no toxicity and reduced melanin content in cell-based assays.
BIOORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Laura Fernandez-Lopez, Sergi Roda, Jose L. Gonzalez-Alfonso, Francisco J. Plou, Victor Guallar, Manuel Ferrer
Summary: In this study, a catalytically efficient artificial protease was designed and easily produced. By modifying an esterase site, a proteolytic site was successfully created. The resulting artificial enzyme exhibited efficient hydrolysis activity under suitable conditions and could be used for one-pot cascade synthesis reactions.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Physical
Qi Yu, Patrick E. Schneider, Sharon Hammes-Schiffer
Summary: This study develops a nuclear-electronic orbital multistate density functional theory (NEO-MSDFT) method to describe hydrogen transfer systems. The method is shown to accurately predict hydrogen tunneling splittings. The analytical gradients derived in this study are used to optimize geometries and generate reaction paths for proton transfer reactions. The results demonstrate that quantizing the transferring proton can lower the barrier of the reaction and the proton density and C-O bond lengths play important roles.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Rebecca Schneider, Tobias A. Engesser, Christian Naether, Ingo Krossing, Felix Tuczek
Summary: In this study, Cu-I salts were synthesized and used as catalysts for the conversion of monophenols to o-quinones. The effects of anions and ligands on the catalyst activity were investigated, and it was found that Cu-II-semiquinone complexes can significantly accelerate the reaction, indicating a mononuclear pathway in the oxygenation process.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Biochemistry & Molecular Biology
Jianping Li, Xiaofeng Min, Xi Zheng, Shaohua Wang, Xuetao Xu, Jinbao Peng
Summary: Tyrosinase inhibitors, including cinnamic acid-eugenol esters, especially c27, showed definite inhibitory activity against tyrosinase, which is crucial in melanin production. Compound c27 exhibited the strongest tyrosinase inhibitory activity and could potentially be used as a lead compound in finding tyrosinase inhibitors.
Article
Optics
B. N. Rajasekhar, Vijay Dharmarpu, Asim Kumar Das, Aparna Shastri, A. Veeraiah, Sunanda Krishnakumar
Summary: A spectroscopic study on benzonitrile was conducted to investigate its electronic and vibrational properties. The results revealed rich vibrational spectra and weak Rydberg transitions. The excited electronic states were classified and explained using quantum chemical calculations. Additionally, the equilibrium geometry and ground state vibrational modes were predicted using DFT methodology.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2022)
Article
Chemistry, Medicinal
Federico Ricci, Kristina Schira, Lyna Khettabi, Lisa Lombardo, Salvatore Mirabile, Rosaria Gitto, Montserrat Soler-Lopez, Joerg Scheuermann, Gerhard Wolber, Laura De Luca
Summary: In this study, the development of new inhibitors targeting both human tyrosinase (hTYR) and Agaricus bisporus tyrosinase (AbTYR) was investigated through retrospective and computational analyses combined with experimental data. A compound called MehT-3 showed comparable activity on both enzymes, suggesting its potential as a dual-targeting molecule. The computational results can provide relevant structural information for the development of newer dual-targeting molecules.
EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY
(2023)
Article
Spectroscopy
Nafisur Rahman, Nabila Khalil
Summary: This study investigated the interaction between sulfasalazine (SZ) and the carrier proteins bovine serum albumin (BSA) and human serum albumin (HSA) using fluorescence, absorption, circular dichroism (CD) spectroscopy, and in silico techniques. The results confirmed the formation of complexes between SZ and BSA/HSA. The binding affinity of SZ to BSA and HSA was reported to be in the order of 106 M-1. The study also revealed the main intermolecular forces involved in the complex stabilization and the binding location of SZ in BSA/HSA. Furthermore, structural alterations in the proteins and microenvironmental perturbations were observed after SZ binding.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Computer Science, Artificial Intelligence
Roberto Barbuti, Anna Bernasconi, Roberta Gori, Paolo Milazzo
Summary: This paper characterizes all nth ancestors using a Boolean formula that can be computed in polynomial time, providing new insights into computational complexity investigations. The focus is on determining the existence of a preimage/nth ancestor and finding a preimage/nth ancestor of minimal size, with an aim to solve ancestor problems in polynomial time, in exact or approximate way.
Review
Chemistry, Multidisciplinary
Hannah M. Rhoda, Alexander J. Heyer, Benjamin E. R. Snyder, Dieter Plessers, Max L. Bols, Robert A. Schoonheydt, Bert F. Sels, Edward Solomon
Summary: Second-sphere interactions play a crucial role in the high activity and selectivity of transition-metal-exchanged zeolites, despite the differences in active-site structures compared to metalloenzymes.
Article
Chemistry, Physical
Edward Solomon, Anex Jose
Summary: This paper provides an overview of the unique spectroscopic features of metal sites in biology, reflecting novel geometric and electronic structures imposed by the protein; it introduces the example of the blue copper active site and its significance in biological electron transfer; it also demonstrates the role of the protein in the geometric and electronic structure of the active site.
FARADAY DISCUSSIONS
(2022)
Article
Biochemistry & Molecular Biology
Yang Ha, Sara A. Dille, Augustin Braun, Kyle Colston, Britt Hedman, Keith O. Hodgson, Partha Basu, Edward I. Solomon
Summary: This study investigates the bonding descriptions and geometric structures of oxidized dithiolene complexes bound to low-valent late transition metal ions, such as Zn-II, Cu-I, and Cu-II, using a combination of S K-edge X-ray absorption spectroscopy and density functional theory calculations. The study quantifies the competition between ligand-ligand repulsion and changes in electronic structures in determining the final geometric structures of the complexes.
JOURNAL OF INORGANIC BIOCHEMISTRY
(2022)
Correction
Instruments & Instrumentation
Diego A. Huyke, Ashwin Ramachandran, Oscar Ramirez-Neri, Jose A. Guerrero-Cruz, Leland B. Gee, Augustin Braun, Dimosthenis Sokaras, Brenda Garcia-Estrada, Edward I. Solomon, Britt Hedman, Mario U. Delgado-Jaime, Daniel P. DePonte, Thomas Kroll, Juan G. Santiago
JOURNAL OF SYNCHROTRON RADIATION
(2022)
Article
Multidisciplinary Sciences
Ioannis Kipouros, Agnieszka Stanczak, Jake W. Ginsbach, Prokopis C. Andrikopoulos, Lubomir Rulsek, Edward I. Solomon
Summary: Melanins are important biopolymer pigments that provide photoprotection, and their biosynthesis involves the catalytic role of tyrosinase (Ty). This study combines spectroscopic, kinetic, and computational methods to investigate the mechanism of the rate-limiting step in melanin biosynthesis. The results provide insights into the O-2 activation and reactivity by the active sites of coupled binuclear copper, with implications in biocatalysis.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Physical
Dieter Plessers, Alexander J. Heyer, Hannah M. Rhoda, Max L. Bols, Edward I. Solomon, Robert A. Schoonheydt, Bert F. Sels
Summary: The industrial implementation of a direct methane-to-methanol process would bring about environmental and economic benefits. Copper zeolites can effectively catalyze this reaction at lower temperatures, especially mordenite zeolites which enable high methanol production. By changing the co-cation, a new method for simplifying the material is introduced, allowing for better analysis, which has implications for the study and tuning of heterogeneous catalysts in general.
Article
Chemistry, Multidisciplinary
Bohee Kim, Magdalene T. T. Brueggemeyer, Wesley J. J. Transue, Younwoo Park, Jaeheung Cho, Maxime A. A. Siegler, Edward I. I. Solomon, Kenneth D. D. Karlin
Summary: Lytic polysaccharide monooxygenases are important in converting biomass to biofuel, and recent studies show that their peroxygenase activity using H2O2 as an oxidant is more important than their monooxygenase functionality. New insights into this activity have been described, including ligand-substrate hydroxylation and Fenton-type chemistry reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Jeffrey T. T. Babicz Jr, Melanie S. Rogers, Dory E. DeWeese, Kyle D. Sutherlin, Rahul Banerjee, Lars H. Bottger, Yoshitaka Yoda, Nobumoto Nagasawa, Makina Saito, Shinji Kitao, Masayuki Kurokuzu, Yasuhiro Kobayashi, Kenji Tamasaku, Makoto Seto, John D. Lipscomb, Edward I. Solomon
Summary: The extradiol dioxygenases and intradiol dioxygenases play a crucial role in the carbon cycle by catalyzing oxidative aromatic ring cleavage. This study investigates the mechanisms behind their regiospecificity in cleavage, using EDO and IDO enzymes as models. The results reveal the structural and electronic properties of key intermediates and propose a viable mechanism for intradiol cleavage.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Augustin Braun, Leland B. Gee, Michael W. Mara, Ethan A. Hill, Thomas Kroll, Dennis Nordlund, Dimosthenis Sokaras, Pieter Glatzel, Britt Hedman, Keith O. Hodgson, A. S. Borovik, Michael L. Baker, Edward I. Solomon
Summary: Fe K-edge XAS is widely used for studying high-valent iron intermediates in catalysts. The 4p-mixing into the 3d orbitals complicates the analysis, but understanding it correctly enables deeper insights into the structure and reactivity. This study reveals that the loss of inversion in the equatorial plane leads to 4p mixing into the 3dx2-y2,xy orbitals, providing structural insights for distinguishing 6- vs 5-coordinate active sites. Furthermore, the study investigates the electronic structure of Fe(IV)=O active sites and their reactivity selectivity through O K-edge XAS.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Casey Van Stappen, Huiguang Dai, Anex Jose, Shiliang Tian, Edward I. Solomon, Yi Lu
Summary: This research investigates the influence of the primary and secondary coordination sphere on CuII-catalyzed S-nitrosylation. The study reveals that kinetic competency is correlated with Cu-S bond strength, Cu spin localization, and relative S(p(s)) vs S(p(p)) contributions to the ground state.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Hyeongtaek Lim, Magdalene T. Brueggemeyer, Wesley J. Transue, Katlyn K. Meier, Stephen M. Jones, Thomas Kroll, Dimosthenis Sokaras, Bradley Kelemen, Britt Hedman, Keith O. Hodgson, Edward I. Solomon
Summary: This study investigates the electronic structure of the d(10) Cu(I) active site in LPMO using Kβ X-ray emission spectroscopy (XES). The lack of inversion symmetry in the His-brace site enables the required 3d/p mixing for intensity in the Kβ valence-to-core (VtC) XES spectrum of Cu(I)-LPMO. These Kβ XES data are correlated to density functional theory (DFT) calculations to define the bonding, particularly the frontier molecular orbital (FMO) of the Cu(I) site. These experimentally validated DFT calculations are used to evaluate the reaction coordinate for homolytic cleavage of the H2O2 O-O bond and understand the activation of the geometric and electronic structure of the Cu(I)-LPMO site for rapid reactivity with H2O2.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Asmita Singha, Alina Sekretareva, Lizhi Tao, Hyeongtaek Lim, Yang Ha, Augustin Braun, Stephen M. Jones, Britt Hedman, Keith O. Hodgson, R. David Britt, Daniel J. Kosman, Edward I. Solomon
Summary: In multicopper oxidases (MCOs), the T1 Cu accepts electrons from the substrate and transfers them to the TNC, reducing O-2 to H2O. The literature fails to explain the wide range of T1 potentials in MCOs, ranging from 340 to 780 mV. This study focuses on the difference in potential of the T1 center in Fet3p and Trametes versicolor laccase (TvL) that have the same ligand set, and reveals that second-sphere H-bonding interactions and carboxylate residues significantly lower the T1 potential.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Glenn Blade, Andrew J. Wessel, Karna Terpstra, Liviu M. Mirica
Summary: Two new ligands were synthesized to stabilize copper ions, and their reactions with copper salts resulted in both Cu(II) and Cu(I) complexes. Characterization analysis confirmed the reversible Cu(II)/Cu(I) redox couples of these ligands and complexes. The stability constants, radiolabeling, and cytotoxicity experiments indicated the potential use of these chelators as Cu-64 PET imaging agents in vivo.
Article
Biochemistry & Molecular Biology
Debanjan Bhattacharjee, Jaweria Bakar, Surbhi P. Chitnis, Erin L. Sausville, Kumar Dilip Ashtekar, Brianna E. Mendelson, Kaitlin Long, Joan C. Smith, David E. Heppner, Jason M. Sheltzer
Summary: This study demonstrates that Ralimetinib inhibits EGFR kinase activity and drives its primary anticancer effects. The findings question the value of p38a as an anticancer target and propose a multi-modal approach to uncovering a drug's mechanism-of-action.
CELL CHEMICAL BIOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Ioannis Kipouros, Agnieszka Stanczak, Martin Culka, Erik Andris, Timothy R. Machonkin, Lubomir Rulisek, Edward Solomon
Summary: This study reveals the H-bonding interactions between active-site waters and the mu-eta(2):eta(2)-peroxide of oxy-tyrosinase, and defines their effects on the Cu(ii)(2)O-2 electronic structure and O-2 activation using spectroscopic and computational methods.
CHEMICAL COMMUNICATIONS
(2022)