Article
Biochemistry & Molecular Biology
Hyejin Park, Shannon Eriksson, Warren S. Warren, Qiu Wang
Summary: In this study, novel N-15 and C-13-labeled NO-sensing probes were designed and developed for real-time detection of NO. These probes undergo selective and rapid reaction with NO, generating detectable AZO products that can be monitored using nuclear magnetic resonance signals. The study also compares the performance of N-15 and C-13 nuclei in hyperpolarized reaction-based probes.
BIOORGANIC & MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Runlian Qu, Lu Shan, Qun Sun, Yao Wei, Pengchi Deng, Xiandeng Hou
Summary: A simple, fast, and green method has been established to quantitatively detect isotope labelled compounds in biology and pharmacy using a novel H-1 Nuclear Magnetic Resonance (H-1-NMR) technique. This method removes the coupling between nearby H-1 and C-13, N-15, simplifying the spectrum and enhancing the signal intensity, allowing for the quantitative detection of real polypeptide samples.
Article
Biochemistry & Molecular Biology
Harri A. Heikkinen, Sofia M. Backlund, Hideo Iwai
Summary: Partially labeling samples with 20% 13C and 100% 15N can reduce chemical costs while maintaining structural information, especially for small proteins. The approach simplifies sample preparation and enhances the efficiency of NMR technology in backbone resonance assignments, structure determination, N15-relaxation analysis, and ligand-protein interactions.
Article
Chemistry, Physical
Natalia N. Kuranova, Daria Petrova, Maksim N. Zavalishin, Aleksei N. Kiselev, George A. Gamov
Summary: Hydrazones and Schiff bases are potent metal chelators with various biological activities. This paper collects protonation constant data of these compounds and proposes a chemometric model to describe the protolytic equilibria constants.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Applied
Antonin Lycka
Summary: 15N NMR data is the most suitable method to quantify azo-hydrazo tautomerism, as the nitrogen atoms of the -N--N-/- NH-N= fragments are directly involved in the equilibrium. With the advancement of NMR spectrometer frequencies, it is now possible to measure 1J(15N, 1H) coupling constants and 15N chemical shifts at the natural abundance level of 15N even with routine spectrometers.
Article
Chemistry, Applied
Zdenka Neuerova, Antonin Lycka
Summary: The one- and two-dimensional NMR spectra of benzenediazonium chloride coupling product with 4-R-naphthalene-1-ols were measured and analysed, revealing that the reaction products exist predominantly in hydrazone forms. Contrary to previous studies, it was found that more electron acceptor types of substituents actually cause an increase in hydrazone content in the compounds.
Article
Multidisciplinary Sciences
Abdullah Naiyer, Bushra Khan, Afzal Hussain, Asimul Islam, Mohamed F. Alajmi, Md. Imtaiyaz Hassan, Monica Sundd, Faizan Ahmad
Summary: Cytochrome c is commonly used as a model protein to study protein folding and stability, with Leu94 being conserved in all mammalian cyt c and the L94G mutation being destabilizing. Protein stability is not affected by labeling, as shown by analysis of secondary and tertiary structures using conventional techniques.
SCIENTIFIC REPORTS
(2021)
Article
Multidisciplinary Sciences
Prajakatta Mulay, Cindy Chen, Vijay Krishna
Summary: This study discovered that pyridoxal-5'-phosphate (PLP) has catalytic activity and can breakdown cysteine to produce hydrogen sulfide (H2S) in the absence of enzymes and multivalent metal ions. The reaction of PLP with cysteine forms a thiazolidine product, which can slowly decompose to produce H2S. This research provides important insights into the role of PLP in metabolic pathways.
SCIENTIFIC REPORTS
(2023)
Article
Engineering, Environmental
Yuying Jing, Anja Miltner, Trine Eggen, Matthias Kaestner, Karolina M. Nowak
Summary: This study conducted a microcosm test to simulate the fate of pesticides in planted filters, and found that the presence of planted filters can enhance the degradation and adsorption of pesticides.
Article
Biochemistry & Molecular Biology
Garry W. Buchko, Mowei Zhou, Cat Hoang Vesely, Jinhui Tao, Wendy J. Shaw, Ryan A. Mehl, Richard B. Cooley
Summary: In this study, the researchers successfully expressed and purified C-13-, N-15-labeled murine amelogenin protein with phosphorylation at Ser-16 using a modified genetic code expansion protocol. This protein will be a valuable tool for studying the process of amelogenesis and mineralization.
Article
Microbiology
Shintaro Hara, Naohisa Wada, Sliver Sung-Yun Hsiao, Meng Zhang, Zhihua Bao, Yoshiyuki Iizuka, Der-Chuen Lee, Shusei Sato, Sen-Lin Tang, Kiwamu Minamisawa
Summary: This study demonstrates that type II methanotrophs in the root tissues of paddy rice perform methane oxidation and nitrogen fixation simultaneously at the single-cell level. The findings provide direct evidence of the activities of methanotrophs in root tissues, suggesting that they may provide fixed nitrogen to root systems or depend on different microenvironmental niches.
Review
Chemistry, Multidisciplinary
Nikita V. Chukanov, Roman V. Shchepin, Sameer M. Joshi, Mohammad S. H. Kabir, Oleg G. Salnikov, Alexandra Svyatova, Igor V. Koptyug, Juri G. Gelovani, Eduard Y. Chekmenev
Summary: NMR hyperpolarization techniques greatly increase nuclear spin polarization, leading to significant sensitivity gains for applications in high-resolution NMR spectroscopy and real-time metabolic imaging. Various hyperpolarization techniques exist, with a focus on targeting C-13 and N-15 sites in biocompatible agents. Long T-1 values of these sites allow hyperpolarized states to be retained for extended periods, with SABRE being a versatile low-cost technique for hyperpolarization of N-15 nuclei.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Analytical
Hassiba Outilaft, Caroline Bund, Martial Piotto, Izzie J. Namer
Summary: The use of C-13-labeled molecular probes is crucial for studying altered metabolic pathways in human pathologies. Analyzing the different C-13 isotopologues resulting from these changes is essential for understanding the underlying biological processes. We propose an NMR methodology, conducted under HRMAS conditions, to explore metabolic pathways in unprocessed pathological cells and tissues. This methodology has the potential to advance the study of human pathologies and therapeutic treatments.
ANALYTICAL CHEMISTRY
(2022)
Review
Biochemistry & Molecular Biology
Philipp Innig Aguion, Alexander Marchanka
Summary: MAS ssNMR is an established tool for studying non-soluble or non-crystalline biomolecules, with significant progress in protein studies but challenges in RNA research. Resonance assignment is a critical step in NMR studies, determining the feasibility of structure determination. Recent research focuses on RNA resonance assignment methods and ssNMR secondary structure determination.
FRONTIERS IN MOLECULAR BIOSCIENCES
(2021)
Article
Multidisciplinary Sciences
Jacob B. Holmes, Viktoriia Liu, Bethany G. Caulkins, Eduardo Hilario, Rittik K. Ghosh, Victoria N. Drago, Robert P. Young, Jennifer A. Romero, Adam D. Gill, Paul M. Bogie, Joana Paulino, Xiaoling Wang, Gwladys Riviere, Yuliana K. Bosken, Jochem Struppe, Alia Hassan, Jevgeni Guidoulianov, Barbara Perrone, Frederic Mentink-Vigier, Chia-en A. Chang, Joanna R. Long, Richard J. Hooley, Timothy C. Mueser, Michael F. Dunn, Leonard J. Mueller
Summary: NMR-assisted crystallography, using solid-state NMR, X-ray crystallography, and first-principles computational chemistry, holds great potential for studying enzymology. It provides atomic-level characterization of stable intermediates in enzyme active sites, offering insights into structure and chemical dynamics. In this study, this integrated approach was used to characterize the tryptophan synthase alpha-aminoacrylate intermediate, revealing its detailed structure and reactivity.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Polymer Science
Victor A. Rozentsvet, Nelly A. Sablina, Daria M. Ulyanova, Sergei V. Kostjuk, Peter M. Tolstoy
Summary: The structure of head and end groups of polybutadiene synthesized by anionic polymerization using tert-butyllithium as an initiator was established through NMR spectroscopy, revealing a higher content of 1,4-units in terminal groups compared to the main chain. A new method for quantitatively calculating the content of head and end groups with different microstructures was proposed.
Article
Chemistry, Physical
Andrey Shishov, Firuza Shakirova, Ulyana Markova, Petr Tolstoy, Andrey Bulatov
Summary: In this study, a deep eutectic solvent based on thymol and 4-(dimethylamino)benzaldehyde was synthesized and characterized. The solvent is stable in the presence of water and can be used as a hydrophobic extractant. It was successfully applied to the derivatization and microextraction of urea in human urine and powdered milk samples, reducing sample pretreatment time and simplifying the determination procedure.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Multidisciplinary
V. A. Rozentsvet, D. M. Ulyanova, N. A. Sablina, M. G. Kuznetsova, P. M. Tolstoy
Summary: Cationic polymerization of penta-1,3-diene with catalytic systems containing organoaluminum compounds and isopropyl chloride allows for the synthesis of completely soluble solid polymers with a high yield and softening point ranging from 81 to 91 degrees C. The use of H-1 and C-13 NMR spectroscopy techniques, including T-2 filtering, as well as H-1, C-13 HSQC and HMBC 2D NMR spectroscopy, enables the identification of carbon atoms signals of the head isopropyl groups connected with the 1,4-trans-unit of polypentadiene.
RUSSIAN CHEMICAL BULLETIN
(2022)
Article
Chemistry, Physical
Anton Mazur, Peter Tolstoy, Konstantinos Sotiriadis
Summary: The effects of organic additives, specifically acetic acid and sodium acetate, on the hydration process of Portland-limestone cement pastes were studied using solid-state C-13, Al-27, and Si-29 NMR spectroscopy. The results showed that these additives retard the cement hydration at early age and influence the kinetics of phase formation.
Article
Biochemistry & Molecular Biology
Elena Yu Tupikina, Mark Sigalov, Peter M. Tolstoy
Summary: A computational method for estimating the geometry of two coupled hydrogen bonds with geometries close to linear using NMR parameters was proposed. The method was developed based on the quantum-chemical investigation of complexes formed by oxygen and nitrogen atoms with substituted methanols. The method selects pairs of NMR chemical shifts to determine the geometry of two hydrogen bonds and shows good agreement with direct quantum-chemical calculations.
Article
Biochemistry & Molecular Biology
Edem R. Chakalov, Elena Yu Tupikina, Daniil M. Ivanov, Ekaterina Bartashevich, Peter M. Tolstoy
Summary: This study presents a detailed analysis of electron density in 145 halogen-bonded complexes and demonstrates the possibility of predicting the strength of halogen bonds based on the distance between the minimum values of electron density and molecular electrostatic potential.
Article
Spectroscopy
E. Yu. Tupikina, A. A. Titova, M. V. Kaplanskiy, E. R. Chakalov, M. A. Kostin, P. M. Tolstoy
Summary: This computational work discusses the applicability of IR spectral parameters for evaluations of the OH center dot center dot center dot N hydrogen bond length. Geometries, energies, and IR parameters were calculated for a set of 124 complexes with OH center dot center dot center dot N hydrogen bond formed by combinations of methanol/acetic acid and pyridine (and their fluorine substituted versions) at the MP2/def2-TZVP level of theory. Equations linking several IR parameters (the shift of proton donor group stretching vibration Delta nu(s), increase of its intensity I, the low-frequency hydrogen bond stretching vibration nu(sigma), bending in-plane delta and out-of-plane gamma vibrations) with interatomic distances are proposed, and the robustness and accuracy of these equations are discussed. Additionally, the enthalpy of OH center dot center dot center dot N hydrogen bond formation Delta H was linked with electron density parameters in (3; -1) critical point.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Chemistry, Multidisciplinary
Irina I. Fedorova, Natalia S. Soldatova, Daniil M. Ivanov, Ksenia Nikiforova, Irina S. Aliyarova, Mekhman S. Yusubov, Peter M. Tolstoy, Rosa M. Gomila, Antonio Frontera, Vadim Yu. Kukushkin, Pavel S. Postnikov, Giuseppe Resnati
Summary: This study reports the planarity of the benzothienoiodolium cation and the preorganization it provides for the hydrogen, halogen, and chalcogen bonds formed by the phenyl hydrogen, iodolium iodine, and thienyl sulfur. Crystallographic analysis reveals the coupling of these bonds to a single anion, coordinated via the supramolecular and heteroditopic synthon XB/HB or XB/ChB. The interactions of these synthons act synergistically and result in unusually short chalcogen bonds formed by the thienyl sulfur.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Biochemistry & Molecular Biology
Ilya Khodov, Valentina Sobornova, Valeriya Mulloyarova, Konstantin Belov, Alexey Dyshin, Luis Batista de Carvalho, Peter Tolstoy, Michael Kiselev
Summary: This study investigates the impact of mefenamic acid on the physical and chemical properties of silica aerogels, as well as its influence on the sorption characteristics of the composite material. Through solid state magic angle spinning nuclear magnetic resonance (MAS NMR) and high-pressure C-13 NMR kinetic studies, the presence of mefenamic acid was identified and the kinetic rates of CO2 sorption were measured. Additionally, high-pressure T-1-T-2 relaxation-relaxation correlation spectroscopy (RRCOSY) and high-pressure nuclear Overhauser effect spectroscopy (NOESY) studies were conducted to estimate the relative amount of mefenamic acid in the aerogel's pores and investigate its conformational preference when released from the aerogel.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Physical
Elena Yu. Tupikina, Vladislav O. Korostelev, Danil V. Krutin, Peter M. Tolstoy
Summary: This study computationally investigated the geometry and IR parameters of arsinic acid (H2AsOOH) and its hydrogen-bonded complexes in different media. The effects of the medium on the complexes were examined both implicitly using the IEFPCM model and explicitly by considering hydrogen-bonded complexes with various hydrogen bond donors or acceptors. The results showed that the transition from vacuum to a polar medium caused changes in the geometry and IR parameters of the complexes, with weak hydrogen bonds becoming weaker and strong and medium hydrogen bonds becoming stronger. The preferential solvation of charge-separated structures was identified as the driving force behind these changes.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
E. R. Chakalov, R. P. Shekurov, V. A. Miluykov, P. M. Tolstoy
Summary: The structure of two intramolecular hydrogen-bonded motifs in ferrocene-1,1'-diyl-bisphosphinic acid has been experimentally revealed using NMR spectroscopy. The study also addressed the localization of bridging hydrons and the origins of opposite signs of H/D isotope effects on P-31 NMR chemical shifts in a cyclic dimer and a homoconjugated anion, utilizing DFT calculations.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Vladimir Y. Mikshiev, Peter M. Tolstoy, Elena Yu Tupikina, Aleksandra M. Puzyk, Mikhail A. Vovk
Summary: In this study, for the first time, energetic profiles for the reaction of AmPS with charged and uncharged nucleophiles have been established through quantum-chemical calculations. The structural motifs promoting the decay of the amide bond and decreasing the Gibbs activation energy (Delta G(double dagger)) for nucleophilic attack have been determined for a range of similar AmPSs. The proposed structural modification of the classic AmPS can facilitate the design of a new acylation agent for practical use.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Mikhail V. Dobrynin, Ilya V. Mongilev, Alexey A. Lezov, Igor Perevyazko, Peter M. Tolstoy, Yurii A. Anufrikov, Anna Yu. Shasherina, Petr S. Vlasov, Vadim Yu. Kukushkin, Regina M. Islamova
Summary: Newly obtained amphiphilic glycosilicones, synthesized via catalytic hydrosilylation, are soluble in water and form aggregates. The block-copolymeric structure of these glycosilicones was confirmed by NMR spectroscopy. They exhibit similar critical micelle concentration to commonly used alkylglucoside surfactants.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Organic
Vladimir Y. Mikshiev, Peter M. Tolstoy, Aleksandra M. Puzyk, Sergey O. Kirichenko, Alexander S. Antonov
Summary: Selective heterocyclization leading to 1,2,3,4-tetrahydrobenzo[h]quinazolines from ortho-ketimines of 1,8-bis(dimethylamino)naphthalene (Dmanlms) under acid catalysis has been revealed. The reactivity difference between Dmanlms and N,N-dimethylaniline ortho-ketimine highlights the importance of the second peri-NMe2 group in Dmanlms.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Physical
I. S. Giba, P. M. Tolstoy, V. V. Mulloyarova
Summary: This study experimentally investigated the structure of intermolecular hydrogen-bonded complexes formed between tert-butylphosphonic acid and trimethylpyridine molecules as the simplest model system of the structural motifs in blend proton-conducting polymer membranes based on phosphonic acid residues. The results showed the existence of two structural motifs, 1:2 and 2:2 acid-base complexes, at low temperatures in a polar aprotic environment.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)