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Giese TJ, Zeng J, Lerew L, McCarthy E, Tao Y, Ekesan Ş, York DM. Software Infrastructure for Next-Generation QM/MM-ΔMLP Force Fields. J Phys Chem B 2024; 128:6257-6271. [PMID: 38905451 DOI: 10.1021/acs.jpcb.4c01466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/23/2024]
Abstract
We present software infrastructure for the design and testing of new quantum mechanical/molecular mechanical and machine-learning potential (QM/MM-ΔMLP) force fields for a wide range of applications. The software integrates Amber's molecular dynamics simulation capabilities with fast, approximate quantum models in the xtb package and machine-learning potential corrections in DeePMD-kit. The xtb package implements the recently developed density-functional tight-binding QM models with multipolar electrostatics and density-dependent dispersion (GFN2-xTB), and the interface with Amber enables their use in periodic boundary QM/MM simulations with linear-scaling QM/MM particle-mesh Ewald electrostatics. The accuracy of the semiempirical models is enhanced by including machine-learning correction potentials (ΔMLPs) enabled through an interface with the DeePMD-kit software. The goal of this paper is to present and validate the implementation of this software infrastructure in molecular dynamics and free energy simulations. The utility of the new infrastructure is demonstrated in proof-of-concept example applications. The software elements presented here are open source and freely available. Their interface provides a powerful enabling technology for the design of new QM/MM-ΔMLP models for studying a wide range of problems, including biomolecular reactivity and protein-ligand binding.
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Affiliation(s)
- Timothy J Giese
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Jinzhe Zeng
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Lauren Lerew
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Erika McCarthy
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Yujun Tao
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Şölen Ekesan
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Darrin M York
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
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2
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Liang G, Zhang M. Unveiling the Unusual Mn(CO) 3 Migration in a Manganese Cyclohexenyl Complex by DFT Computations. Molecules 2024; 29:2945. [PMID: 38931010 PMCID: PMC11206625 DOI: 10.3390/molecules29122945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 06/18/2024] [Accepted: 06/18/2024] [Indexed: 06/28/2024] Open
Abstract
Homogeneous catalysis involving a transition metal agostic interaction (TM…H…C) is an attractive strategy for C-H bond activation, in which the transition metal agostic intermediates serve as the critical component. To investigate the roles of manganese agostic intermediates in the unusual migration of the Mn(CO)3 fragment in the (exo-phenyl)(η3-cyclohexenyl)manganese tricarbonyl [(Ph)(η3-C6H8)Mn(CO)3] (complex 1) under the protonation of tetrafluoroboric acid-diethyl ether (HBF4.Et2O), a comprehensive density functional theory (DFT) theoretical study was performed. The computational results showed that formation of the [(cyclohex-3-enyl)-η6-benzene]manganese tricarbonyl complex [(C6H9)(η6-Ph)Mn(CO)3+][BF4] (complex 2) was achieved via a series of mono-agostic and di-agostic intermediates. The overall rate-limiting step for this unusual migration of the Mn(CO)3 fragment is the formation of the di-agostic (η2-phenyl)manganese complex 8 (4 → 5 → 8) with a Gibbs barrier of 15.4 kcal mol-1. The agostic intermediates with TM…H…C agostic interactions were well-characterized by geometry parameters, Atoms-In-Molecules (AIM) analyses, and the Natural Adaptive Orbitals (NAdOs). The located pathways in the current study successfully explained the experimental observations, and the findings on the TM…H…C agostic interaction provided a new aspect of the catalytic reaction with the manganese complex.
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Affiliation(s)
- Guangchao Liang
- Academy of Advanced Interdisciplinary Research, Xidian University, Xi’an 710071, China
| | - Min Zhang
- Department of Pharmacy, School of Medicine, Xi’an International University, Xi’an 710077, China;
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Usher ET, Fossat MJ, Holehouse AS. Phosphorylation of disordered proteins tunes local and global intramolecular interactions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.10.598315. [PMID: 38915510 PMCID: PMC11195077 DOI: 10.1101/2024.06.10.598315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Protein post-translational modifications, such as phosphorylation, are important regulatory signals for diverse cellular functions. In particular, intrinsically disordered protein regions (IDRs) are subject to phosphorylation as a means to modulate their interactions and functions. Toward understanding the relationship between phosphorylation in IDRs and specific functional outcomes, we must consider how phosphorylation affects the IDR conformational ensemble. Various experimental techniques are suited to interrogate the features of IDR ensembles; molecular simulations can provide complementary insights and even illuminate ensemble features that may be experimentally inaccessible. Therefore, we sought to expand the tools available to study phosphorylated IDRs by all-atom Monte Carlo simulations. To this end, we implemented parameters for phosphoserine (pSer) and phosphothreonine (pThr) into the OPLS version of the continuum solvent model, ABSINTH, and assessed their performance in all-atom simulations compared to published findings. We simulated short (< 20 residues) and long (> 80 residues) phospho-IDRs that, collectively, survey both local and global phosphorylation-induced changes to the ensemble. Our simulations of four well-studied phospho-IDRs show near-quantitative agreement with published findings for these systems via metrics including changes to radius of gyration, transient helicity, and persistence length. We also leveraged the inherent advantage of sequence control in molecular simulations to explore the conformational effects of diverse combinations of phospho-sites in two multi-phosphorylated IDRs. Our results support and expand on prior observations that connect phosphorylation to changes in the IDR conformational ensemble. Herein, we describe phosphorylation as a means to alter sequence chemistry, net charge and charge patterning, and intramolecular interactions, which can collectively modulate the local and global IDR ensemble features.
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Affiliation(s)
- Emery T. Usher
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Biomolecular Condensates (CBC), Washington University in St. Louis, St. Louis, MO, USA
| | - Martin J. Fossat
- Department of Biological Physics, Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Alex S. Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Biomolecular Condensates (CBC), Washington University in St. Louis, St. Louis, MO, USA
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4
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Ould Mohamed L, Abtouche S, Ghoualem Z, Assfeld X. Unraveling redox pathways of the disulfide bond in dimethyl disulfide: Ab initio modeling. J Mol Model 2024; 30:180. [PMID: 38780881 DOI: 10.1007/s00894-024-05963-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 05/03/2024] [Indexed: 05/25/2024]
Abstract
CONTEXT In cellular environments, the reduction of disulfide bonds is pivotal for protein folding and synthesis. However, the intricate enzymatic mechanisms governing this process remain poorly understood. This study addresses this gap by investigating a disulfide bridge reduction reaction, serving as a model for comprehending electron and proton transfer in biological systems. Six potential mechanisms for reducing the dimethyl disulfide (DMDS) bridge through electron and proton capture were explored. Thermodynamic and kinetic analyses elucidated the sequence of proton and electron addition. MD-PMM, a method that combines molecular dynamics simulations and quantum-chemical calculations, was employed to compute the redox potential of the mechanism. This research provides valuable insights into the mechanisms and redox potentials involved in disulfide bridge reduction within proteins, offering an understanding of phenomena that are challenging to explore experimentally. METHODS All calculations used the Gaussian 09 software package at the MP2/6-311 + g(d,p) theory level. Visualization of the molecular orbitals and electron densities was conducted using Gaussview6. Molecular dynamics simulations were performed using GROMACS with the CHARMM36 force field. The PyMM program (Python Program for QM/MM Simulations Based on the Perturbed Matrix Method) is used to apply the Perturbed Matrix Method to MD simulations.
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Affiliation(s)
- Lina Ould Mohamed
- Laboratoire de Physico Chimie Théorique Et Chimie Informatique, LPCTCI, Faculté de Chimie, USTHB, 16111, Algiers, Algeria
| | - Soraya Abtouche
- Laboratoire de Physico Chimie Théorique Et Chimie Informatique, LPCTCI, Faculté de Chimie, USTHB, 16111, Algiers, Algeria.
| | - Zeyneb Ghoualem
- Laboratoire de Physico Chimie Théorique Et Chimie Informatique, LPCTCI, Faculté de Chimie, USTHB, 16111, Algiers, Algeria
| | - Xavier Assfeld
- Physique et Chimie Théoriques, UMR 7019, Faculté des Sciences et Technologies, Université de Lorraine, BP 70239, 54506, Vandoeuvre Lès Nancy Cedex, France
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5
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Beckett D, El-Baba TJ, Zhang Z, Clemmer DE, Raghavachari K. Tautomerization of H +KPGG: Entropic Consequences of Strong Hydrogen-Bond Networks in Peptides. J Phys Chem A 2023; 127:6282-6291. [PMID: 37490716 PMCID: PMC10405267 DOI: 10.1021/acs.jpca.3c03744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/11/2023] [Indexed: 07/27/2023]
Abstract
Ion mobility spectrometry-mass spectrometry and quantum chemical calculations are used to determine the structures and stabilities of the singly protonated peptide H+KPGG. The two peaks making up the IMS distribution are shown to be tautomers differing by the location of the extra proton on either the lysine side chain or the N-terminus. The lysine-protonated tautomer is strongly preferred entropically while being disfavored in terms of the electronic energy and enthalpy. This relationship is shown, through comparison of all low-lying conformers of both tautomers, to be related to the strong hydrogen-bond network of the N-terminally protonated tautomer. A general relationship is demonstrated wherein stronger cross-peptide hydrogen-bond networks result in entropically disfavored conformers. Further effects of the H+KPGG hydrogen-bond network are probed by computationally examining singly and doubly methylated analogues. These results demonstrate the importance of the entropic consequences of hydrogen bonds to peptide stability as well as techniques for perturbing the hydrogen-bond network and folding preferences of peptides via minimal chemical modification.
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Affiliation(s)
- Daniel Beckett
- Department
of Chemistry, Chicago Center for Theoretical Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
- Department
of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Tarick J. El-Baba
- Department
of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Zhichao Zhang
- Department
of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - David E. Clemmer
- Department
of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Krishnan Raghavachari
- Department
of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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6
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McCarthy E, Ekesan Ş, Giese TJ, Wilson TJ, Deng J, Huang L, Lilley DJ, York DM. Catalytic mechanism and pH dependence of a methyltransferase ribozyme (MTR1) from computational enzymology. Nucleic Acids Res 2023; 51:4508-4518. [PMID: 37070188 PMCID: PMC10201425 DOI: 10.1093/nar/gkad260] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/09/2023] [Accepted: 04/10/2023] [Indexed: 04/19/2023] Open
Abstract
A methyltransferase ribozyme (MTR1) was selected in vitro to catalyze alkyl transfer from exogenous O6-methylguanine (O6mG) to a target adenine N1, and recently, high-resolution crystal structures have become available. We use a combination of classical molecular dynamics, ab initio quantum mechanical/molecular mechanical (QM/MM) and alchemical free energy (AFE) simulations to elucidate the atomic-level solution mechanism of MTR1. Simulations identify an active reactant state involving protonation of C10 that hydrogen bonds with O6mG:N1. The deduced mechanism involves a stepwise mechanism with two transition states corresponding to proton transfer from C10:N3 to O6mG:N1 and rate-controlling methyl transfer (19.4 kcal·mol-1 barrier). AFE simulations predict the pKa for C10 to be 6.3, close to the experimental apparent pKa of 6.2, further implicating it as a critical general acid. The intrinsic rate derived from QM/MM simulations, together with pKa calculations, enables us to predict an activity-pH profile that agrees well with experiment. The insights gained provide further support for a putative RNA world and establish new design principles for RNA-based biochemical tools.
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Affiliation(s)
- Erika McCarthy
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Şölen Ekesan
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Timothy J Giese
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Timothy J Wilson
- Nucleic Acid Structure Research Group, MSI/WTB Complex, The University of Dundee, Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Jie Deng
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong–Hong Kong Joint Laboratory for RNA Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
| | - Lin Huang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Guangdong–Hong Kong Joint Laboratory for RNA Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
| | - David M J Lilley
- Nucleic Acid Structure Research Group, MSI/WTB Complex, The University of Dundee, Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Darrin M York
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
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7
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Moore CC, Staroverov VN, Konermann L. Using Density Functional Theory for Testing the Robustness of Mobile-Proton Molecular Dynamics Simulations on Electrosprayed Ions: Structural Implications for Gaseous Proteins. J Phys Chem B 2023; 127:4061-4071. [PMID: 37116098 DOI: 10.1021/acs.jpcb.3c01581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Current experiments only provide low-resolution information on gaseous protein ions generated by electrospray ionization (ESI). Molecular dynamics (MD) simulations can yield complementary insights. Unfortunately, conventional MD does not capture the mobile nature of protons in gaseous proteins. Mobile-proton MD (MPMD) overcomes this limitation. Earlier MPMD data at 300 K indicated that protein ions generated by "native" ESI retain solution-like structures with a hydrophobic core and zwitterionic exterior [Bakhtiari, M.; Konermann, L. J. Phys. Chem. B 2019, 123, 1784-1796]. MPMD redistributes protons using electrostatic and proton affinity calculations. The robustness of this approach has never been scrutinized. Here, we close this gap by benchmarking MPMD against density functional theory (DFT) at the B3LYP/6-31G* level, which is well suited for predicting proton affinities. The computational cost of DFT necessitated the use of small peptides. The MPMD energetic ranking of proton configurations was found to be consistent with DFT single-point energies, implying that MPMD can reliably identify favorable protonation sites. Peptide MPMD runs converged to DFT-optimized structures only when applying 300-500 K temperature cycling, which was necessary to prevent trapping in local minima. Temperature cycling MPMD was then applied to gaseous protein ions. Native ubiquitin converted to slightly expanded structures with a zwitterionic core and a nonpolar exterior. Our data suggest that such inside-out protein structures are intrinsically preferred in the gas phase, and that they form in ESI experiments after moderate collisional excitation. This is in contrast to native ESI (with minimal collisional excitation, simulated by MPMD at 300 K), where kinetic trapping promotes the survival of solution-like structures. In summary, this work validates the MPMD approach for simulations on gaseous peptides and proteins.
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Affiliation(s)
- Conrad C Moore
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Viktor N Staroverov
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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8
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Souza JNDPE, da Silva RM, Fortes SS, de Oliveira ARM, Ferreira LS, Vessecchi R, Lopes NP, Silva DB. Oxidation Products from the Neolignan Licarin A by Biomimetic Reactions and Assessment of in vivo Acute Toxicity. PLANTA MEDICA 2023. [PMID: 36889328 DOI: 10.1055/a-2009-0732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Licarin A, a dihydrobenzofuranic neolignan presents in several medicinal plants and seeds of nutmeg, exhibits strong activity against protozoans responsible for Chagas disease and leishmaniasis. From biomimetic reactions by metalloporphyrin and Jacobsen catalysts, seven products were determined: four isomeric products yielded by epoxidation from licarin A, besides a new product yielded by a vicinal diol, a benzylic aldehyde, and an unsaturated aldehyde in the structure of the licarin A. The incubation with rat and human liver microsomes partially reproduced the biomimetic reactions by the production of the same epoxidized product of m/z 343 [M + H]+. In vivo acute toxicity assays of licarin A suggested liver toxicity based on biomarker enzymatic changes. However, microscopic analysis of tissues sections did not show any tissue damage as indicative of toxicity after 14 days of exposure. New metabolic pathways of the licarin A were identified after in vitro biomimetic oxidation reaction and in vitro metabolism by rat or human liver microsomes.
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Affiliation(s)
- Juliana Neves de Paula E Souza
- Núcleo de Pesquisa em Produtos Naturais e Sintéticos (NPPNS), Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Rodrigo Moreira da Silva
- Núcleo de Pesquisa em Produtos Naturais e Sintéticos (NPPNS), Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Simone Silveira Fortes
- Departamento de Química, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Leandro S Ferreira
- Núcleo de Pesquisa em Produtos Naturais e Sintéticos (NPPNS), Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
- Departamento de Farmácia, Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN, Brazil
| | - Ricardo Vessecchi
- Departamento de Química, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Norberto Peporine Lopes
- Núcleo de Pesquisa em Produtos Naturais e Sintéticos (NPPNS), Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Denise Brentan Silva
- Núcleo de Pesquisa em Produtos Naturais e Sintéticos (NPPNS), Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
- Laboratório de Produtos Naturais e Espectrometria de Massas (LAPNEM), Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição (FACFAN), Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil
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9
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Zeng J, Tao Y, Giese TJ, York DM. QDπ: A Quantum Deep Potential Interaction Model for Drug Discovery. J Chem Theory Comput 2023; 19:1261-1275. [PMID: 36696673 PMCID: PMC9992268 DOI: 10.1021/acs.jctc.2c01172] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We report QDπ-v1.0 for modeling the internal energy of drug molecules containing H, C, N, and O atoms. The QDπ model is in the form of a quantum mechanical/machine learning potential correction (QM/Δ-MLP) that uses a fast third-order self-consistent density-functional tight-binding (DFTB3/3OB) model that is corrected to a quantitatively high-level of accuracy through a deep-learning potential (DeepPot-SE). The model has the advantage that it is able to properly treat electrostatic interactions and handle changes in charge/protonation states. The model is trained against reference data computed at the ωB97X/6-31G* level (as in the ANI-1x data set) and compared to several other approximate semiempirical and machine learning potentials (ANI-1x, ANI-2x, DFTB3, MNDO/d, AM1, PM6, GFN1-xTB, and GFN2-xTB). The QDπ model is demonstrated to be accurate for a wide range of intra- and intermolecular interactions (despite its intended use as an internal energy model) and has shown to perform exceptionally well for relative protonation/deprotonation energies and tautomers. An example application to model reactions involved in RNA strand cleavage catalyzed by protein and nucleic acid enzymes illustrates QDπ has average errors less than 0.5 kcal/mol, whereas the other models compared have errors over an order of magnitude greater. Taken together, this makes QDπ highly attractive as a potential force field model for drug discovery.
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Affiliation(s)
- Jinzhe Zeng
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Yujun Tao
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Timothy J. Giese
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
| | - Darrin M. York
- Laboratory for Biomolecular Simulation Research, Institute for Quantitative Biomedicine and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA
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10
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Nacsa AB, Czakó G. Benchmark Ab Initio Determination of the Conformers, Proton Affinities, and Gas-Phase Basicities of Cysteine. J Phys Chem A 2022; 126:9667-9679. [PMID: 36524999 PMCID: PMC9806835 DOI: 10.1021/acs.jpca.2c07035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A systematic conformational mapping combined with literature data leads to 85 stable neutral cysteine conformers. The implementation of the same mapping process for the protonated counterparts reveals 21 N-(amino-), 64 O-(carbonyl-), and 37 S-(thiol-)protonated cysteine conformers. Their relative energies and harmonic vibrational frequencies are given at the MP2/aug-cc-pVDZ level of theory. Further benchmark ab initio computations are performed for the 10 lowest-lying neutral and protonated amino acid conformers (for each type) such as CCSD(T)-F12a/cc-pVDZ-F12 geometry optimizations (and frequency computations for cysteine) as well as auxiliary correction computations of the basis set effects up to CCSD(T)-F12b/cc-pVQZ-F12, electron correlation effects up to CCSDT(Q), core correlation effects, second-order Douglass-Kroll relativistic effects, and zero-point energy contributions. Boltzmann-averaged 0 (298.15) K proton affinity and [298.15 K gas-phase basicity] values of cysteine are predicted to be 214.96 (216.39) [208.21], 201.83 (203.55) [194.16], and 193.31 (194.74) [186.40] kcal/mol for N-, O-, and S-protonation, respectively, also considering the previously described auxiliary corrections.
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11
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Fereydooni Naghani F, Emamian S, Zare K. A comprehensive theoretical analysis on the intermolecular hydrogen bond interactions with the Lewis bases having multiple hydrogen bonding ability. J PHYS ORG CHEM 2022. [DOI: 10.1002/poc.4357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - Saeedreza Emamian
- Chemistry Department, Shahrood Branch Islamic Azad University Shahrood Iran
| | - Karim Zare
- Department of Chemistry, Science and Research Branch Islamic Azad University Tehran Iran
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12
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Denis EH, Bade JL, Renslow RS, Morrison KA, Nims MK, Govind N, Ewing RG. Proton Affinity Values of Fentanyl and Fentanyl Analogues Pertinent to Ambient Ionization and Detection. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:482-490. [PMID: 35041405 DOI: 10.1021/jasms.1c00320] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Proton affinity is a major factor in the atmospheric pressure chemical ionization of illicit drugs. The detection of illicit drugs by mass spectrometry and ion mobility spectrometry relies on the analytes having greater proton affinities than background species. Evaluating proton affinities for fentanyl and its analogues is informative for predicting the likelihood of ionization in different environments and for optimizing the compounds' ionization and detection, such as through the addition of dopant chemicals. Herein, density functional theory was used to computationally determine the proton affinity and gas-phase basicity of 15 fentanyl compounds and several relevant molecules as a reference point. The range of proton affinities for the fentanyl compounds was from 1018 to 1078 kJ/mol. Fentanyl compounds with the higher proton affinity values appeared to form a bridge between the oxygen on the amide and the protonated nitrogen on the piperidine ring based on models and calculated bond distances. Experiments with fragmentation of proton-bound clusters using atmospheric flow tube-mass spectrometry (AFT-MS) provided estimates of relative proton affinities and showed proton affinity values of fentanyl compounds >1000 kJ/mol, which were consistent with the computational results. The high proton affinities of fentanyl compounds facilitate their detection by ambient ionization techniques in complex environments. The detection limits of the fentanyl compounds with AFT-MS are in the low femtogram range, which demonstrates the feasibility of trace vapor drug detection.
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Affiliation(s)
- Elizabeth H Denis
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Jessica L Bade
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Ryan S Renslow
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Kelsey A Morrison
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Megan K Nims
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Niranjan Govind
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Robert G Ewing
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
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13
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Altowyan MS, Soliman SM, Lasri J, Eltayeb NE, Haukka M, Barakat A, El-Faham A. A New Pt(II) Complex with Anionic s-Triazine Based NNO-Donor Ligand: Synthesis, X-ray Structure, Hirshfeld Analysis and DFT Studies. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27051628. [PMID: 35268727 PMCID: PMC8911880 DOI: 10.3390/molecules27051628] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/22/2022] [Accepted: 02/25/2022] [Indexed: 12/02/2022]
Abstract
The reaction of PtCl2 with s-triazine-type ligand (HTriaz) (1:1) in acetone under heating afforded a new [Pt(Triaz)Cl] complex. Single-crystal X-ray diffraction analysis showed that the ligand (HTriaz) is an NNO tridentate chelate via two N-atoms from the s-triazine and hydrazone moieties and one oxygen from the deprotonated phenolic OH. The coordination environment of the Pt(II) is completed by one Cl−1 ion trans to the Pt-N(hydrazone). Hirshfeld surface analysis showed that the most dominant interactions are the H···H, H···C and O···H intermolecular contacts. These interactions contributed by 60.9, 11.2 and 8.3% from the whole fingerprint area, respectively. Other minor contributions from the Cl···H, C···N, N···H and C···C contacts were also detected. Among these interactions, the most significant contacts are the O···H, H···C and H···H interactions. The amounts of the electron transfer from the ligand groups to Pt(II) metal center were predicted using NBO calculations. Additionally, the electronic spectra were assigned based on the TD-DFT calculations.
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Affiliation(s)
- Mezna Saleh Altowyan
- Department of Chemistry, College of Science, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia;
| | - Saied M. Soliman
- Department of Chemistry, Faculty of Science, Alexandria University, P.O. Box 426, Ibrahimia, Alexandria 21321, Egypt;
- Correspondence: (S.M.S.); (J.L.); (A.B.)
| | - Jamal Lasri
- Department of Chemistry, Rabigh College of Science and Arts, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
- Correspondence: (S.M.S.); (J.L.); (A.B.)
| | - Naser E. Eltayeb
- Department of Chemistry, Rabigh College of Science and Arts, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
| | - Matti Haukka
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland;
| | - Assem Barakat
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
- Correspondence: (S.M.S.); (J.L.); (A.B.)
| | - Ayman El-Faham
- Department of Chemistry, Faculty of Science, Alexandria University, P.O. Box 426, Ibrahimia, Alexandria 21321, Egypt;
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14
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Camacho-Mojica DC, Ha JK, Min SK, Vianello R, Ruoff RS. Proton affinity and gas phase basicity of diamandoid molecules: diamantane to C 131H 116. Phys Chem Chem Phys 2022; 24:3470-3477. [PMID: 35076039 DOI: 10.1039/d1cp04177k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calculated proton affinities (PAs) and gas phase basicities (GPBs) are reported for diamantane (C14H20), triamantane (C18H24), 'globular and planar' isomers of tetramantane (C22H28) and pentamantane (C26H32), and for one 'globular' isomer of each of the larger diamondoid molecules: C51H58, C78H72, C102H90, and C131H116. Assuming CxHy as the parent diamondoid molecule, we calculated PA and GPB values for a variety of CxHy+1+ isomers, as well as for the reaction CxHy + H+ yielding CxHy-1+ + H2(g); the latter is slightly favored based on GPB values for diamantane through pentamantane, but less favored compared to certain CxHy+1+ isomers of C51H58, C102H90, and C131H116. Indeed, the GPB values of C51H58, C102H90, and C131H116 classifiy them as 'superbases'. Calculations that had the initial location of the proton in an interstitial site inside the diamondoid molecule always showed the H having moved to the outside of the diamondoid molecule; for this reason, we focused on testing a variety of initial configurations with the proton placed in an initial position on the surface. Additional protons were added to determine the limiting number that could be, per these calculations, taken up by the diamondoid molecules and the maximum number of protons are shown in parentheses: C14H20(2), C18H24(3), C22H28(3), C26H32(3), C51H58(4). Bader charge distributions obtained for CxHy+1+ isomers (for diamantane through pentamantane) suggest that the positive charge is essentially completely delocalized over all the H atoms. NMR spectra were calculated for different isomers of C14H19+, and compared to the published NMR spectrum for when diamantane was mixed with magic acid and H2(g) was produced.
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Affiliation(s)
- Dulce C Camacho-Mojica
- Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea.
| | - Jong-Kwon Ha
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Seung Kyu Min
- Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea. .,Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
| | - Robert Vianello
- Laboratory for the Computational Design and Synthesis of Functional Materials, Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, 10 000 Zagreb, Croatia
| | - Rodney S Ruoff
- Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea. .,Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea.,Department Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea.,School of Chemical Engineering and Energy Science, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
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15
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Corinti D, Chiavarino B, Spano M, Tintaru A, Fornarini S, Crestoni ME. Molecular Basis for the Remarkably Different Gas-Phase Behavior of Deprotonated Thyroid Hormones Triiodothyronine (T3) and Reverse Triiodothyronine (rT3): A Clue for Their Discrimination? Anal Chem 2021; 93:14869-14877. [PMID: 34714056 PMCID: PMC8581966 DOI: 10.1021/acs.analchem.1c03892] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Thyroid hormones
are biologically active small molecules responsible
for growth and development regulation, basal metabolic rate, and lipid
and carbohydrate metabolism. Liquid chromatography mass spectrometry
(LC–MS) can be used to quantify thyroid hormones blood level
with high speed and selectivity, aiming to improve the diagnosis and
treatment of the severe pathological conditions in which they are
implicated, i.e., hypo- and hyperthyroidism. In this work, the gas-phase
behavior of the isomeric thyroid hormones triiodothyronine (T3) and
reverse triiodothyronine (rT3) in their deprotonated form was studied
at a molecular level using MS-based techniques. Previously reported
collision-induced dissociation experiments yielded distinct spectra
despite the high structural similarity of the two compounds, suggesting
different charge sites to be responsible. Infrared multiple photon
dissociation spectroscopy on [T3-H]− and [rT3-H]− was performed, and the results were interpreted using
DFT and MP2 calculations, assessing the prevalence of T3 in the carboxylate
form and rT3 as a phenolate isomer. The different deprotonation sites
of the two isomers were also found to drive their ion-mobility behavior.
In fact, [T3-H]− and [rT3-H]− were
successfully separated. Drift times were correlated with collisional
cross section values of 209 and 215 Å2 for [T3-H]− and [rT3-H]−, respectively. Calculations
suggested the charge site to be the main parameter involved in the
different mobilities of the two anions. Finally, bare [T3-H]− and [rT3-H]− were made to react with neutral acetylacetone
and trifluoroacetic acid, confirming rT3 to be more acidic than T3
in agreement with the calculated gas-phase acidities of T3 and rT3
equal to 1345 and 1326 kJ mol–1, respectively.
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Affiliation(s)
- Davide Corinti
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", Roma I-00185, Italy
| | - Barbara Chiavarino
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", Roma I-00185, Italy
| | - Mattia Spano
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", Roma I-00185, Italy
| | - Aura Tintaru
- Aix Marseille Univ, CNRS, Institut de Chimie Radicalaire, UMR 7273, Marseille 13397, France
| | - Simonetta Fornarini
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", Roma I-00185, Italy
| | - Maria Elisa Crestoni
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", Roma I-00185, Italy
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16
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Prasad S, Tantillo DJ. Substituent Effects on the Basicity of Patriscabrin A and Lettucenin A: Evolution Favors the Aromatic? ACS OMEGA 2021; 6:29685-29691. [PMID: 34778640 PMCID: PMC8582057 DOI: 10.1021/acsomega.1c04051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/18/2021] [Indexed: 05/06/2023]
Abstract
Basicities for derivatives of patriscabrin A and lettucenin A were calculated with density functional theory. A significant correlation is observed between the basicity and Hammett σ parameters. Protonation increases the aromatic character of the cyclic moieties of each natural product. The naturally occurring structures are predicted to be the most aromatic.
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17
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Zhu Q, Png ZM, Lin T, Loh XJ, Tang T, Xu J. Synthesis and Halochromic Properties of 1,2,6-Tri- and 1,2,3,6-Tetra-aryl Azulenes. Chempluschem 2021; 86:1116-1122. [PMID: 34402212 DOI: 10.1002/cplu.202100261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/22/2021] [Indexed: 11/06/2022]
Abstract
A series of novel 2,6-functionalized azulene molecules Azu1-3 with varied fluorene substituents at the 1- and 3-positions of azulene as well as at the 5'-position of 2-thiophene group were synthesized. Their electronic absorption and emission spectra at neutral and protonated states were examined. It was found that after functionalization with fluorenyl groups, Azu1-3 exhibited absorption maxima at 445, 451 to 468 nm, respectively. In contrast, their corresponding protonated species showed much redshifted absorption maxima at 560, 582 to 643 nm, respectively, mainly due to the extension of conjugation length and the large dipole moment along the C2v axis of 2,6-substituted azulene molecules. Azu1-3 are non-fluorescent in their neutral forms, but became emissive in their protonated states. Analysis of absorption and emission spectra shows that substitution of the 1- or 3-position of azulene led to decrease in response to trifluoroacetic acid.
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Affiliation(s)
- Qiang Zhu
- Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore
| | - Zhuang Mao Png
- Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore
| | - Tingting Lin
- Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore
| | - Xian Jun Loh
- Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore
| | - Tao Tang
- Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore
| | - Jianwei Xu
- Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore, 138634, Singapore.,Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
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18
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Abstract
A systematic conformational search reveals three N- (amino) and eight O- (carbonyl) protonated glycine conformers with benchmark equilibrium(adiabatic) relative energies in the 0.00-7.51(0.00-7.37) and 25.91-31.61(24.45-30.28) kcal mol-1 ranges, respectively. Benchmark ab initio structures of the glycine conformers and its protonated species are obtained at the CCSD(T)-F12b/aug-cc-pVTZ level of theory and the relative energy computations consider basis-set effects up to aug-cc-pVQZ with CCSD(T)-F12b, electron correlation up to CCSDT(Q), core correlation corrections, scalar relativistic effects, and zero-point energy contributions. The best predictions for Boltzmann-averaged 0(298.15) K proton affinities and [298.15 K gas-phase basicities] of glycine are 211.00(212.43)[204.75] and 186.38(187.64)[180.21] kcal mol-1 for N- and O-protonation, respectively, in excellent agreement with experiments.
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Affiliation(s)
- András B Nacsa
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged H-6720, Hungary.
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19
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Borges R, Colby SM, Das S, Edison AS, Fiehn O, Kind T, Lee J, Merrill AT, Merz KM, Metz TO, Nunez JR, Tantillo DJ, Wang LP, Wang S, Renslow RS. Quantum Chemistry Calculations for Metabolomics. Chem Rev 2021; 121:5633-5670. [PMID: 33979149 PMCID: PMC8161423 DOI: 10.1021/acs.chemrev.0c00901] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Indexed: 02/07/2023]
Abstract
A primary goal of metabolomics studies is to fully characterize the small-molecule composition of complex biological and environmental samples. However, despite advances in analytical technologies over the past two decades, the majority of small molecules in complex samples are not readily identifiable due to the immense structural and chemical diversity present within the metabolome. Current gold-standard identification methods rely on reference libraries built using authentic chemical materials ("standards"), which are not available for most molecules. Computational quantum chemistry methods, which can be used to calculate chemical properties that are then measured by analytical platforms, offer an alternative route for building reference libraries, i.e., in silico libraries for "standards-free" identification. In this review, we cover the major roadblocks currently facing metabolomics and discuss applications where quantum chemistry calculations offer a solution. Several successful examples for nuclear magnetic resonance spectroscopy, ion mobility spectrometry, infrared spectroscopy, and mass spectrometry methods are reviewed. Finally, we consider current best practices, sources of error, and provide an outlook for quantum chemistry calculations in metabolomics studies. We expect this review will inspire researchers in the field of small-molecule identification to accelerate adoption of in silico methods for generation of reference libraries and to add quantum chemistry calculations as another tool at their disposal to characterize complex samples.
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Affiliation(s)
- Ricardo
M. Borges
- Walter
Mors Institute of Research on Natural Products, Federal University of Rio de Janeiro, Rio de Janeiro 21941-901, Brazil
| | - Sean M. Colby
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
| | - Susanta Das
- Department
of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Arthur S. Edison
- Departments
of Genetics and Biochemistry and Molecular Biology, Complex Carbohydrate
Research Center and Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602, United States
| | - Oliver Fiehn
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
| | - Tobias Kind
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
| | - Jesi Lee
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Amy T. Merrill
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Kenneth M. Merz
- Department
of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Thomas O. Metz
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
| | - Jamie R. Nunez
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
| | - Dean J. Tantillo
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Lee-Ping Wang
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Shunyang Wang
- West
Coast Metabolomics Center for Compound Identification, UC Davis Genome
Center, University of California, Davis, California 95616, United States
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Ryan S. Renslow
- Biological
Science Division, Pacific Northwest National
Laboratory, Richland, Washington 99352, United States
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20
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Burgoyne ED, Molina-Osorio AF, Moshrefi R, Shanahan R, McGlacken GP, Stockmann TJ, Scanlon MD. Detection of Pseudomonas aeruginosa quorum sensing molecules at an electrified liquid|liquid micro-interface through facilitated proton transfer. Analyst 2021; 145:7000-7008. [PMID: 32869782 DOI: 10.1039/d0an01245a] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Miniaturization of electrochemical detection methods for point-of-care-devices is ideal for their integration and use within healthcare environments. Simultaneously, the prolific pathogenic bacteria Pseudomonas aeruginosa poses a serious health risk to patients with compromised immune systems. Recognizing these two factors, a proof-of-concept electrochemical method employing a micro-interface between water and oil (w/o) held at the tip of a pulled borosilicate glass capillary is presented. This method targets small molecules produced by P. aeruginosa colonies as signalling factors that control colony growth in a pseudo-multicellular process known as quorum sensing (QS). The QS molecules of interest are 4-hydroxy-2-heptylquinoline (HHQ) and 2-heptyl-3,4-dihydroxyquinoline (PQS, Pseudomonas quinolone signal). Hydrophobic HHQ and PQS molecules, dissolved in the oil phase, were observed electrochemically to facilitate proton transfer across the w/o interface. This interfacial complexation can be exploited as a facile electrochemical detection method for P. aeruginosa and is advantageous as it does not depend on the redox activity of HHQ/PQS. Interestingly, the limit-of-linearity is reached as [H+] ≈ [ligand]. Density functional theory calculations were performed to determine the proton affinities and gas-phase basicities of HHQ/PQS, as well as elucidate the likely site of stepwise protonation within each molecule.
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Affiliation(s)
- Edward D Burgoyne
- The Bernal Institute and Department of Chemical Sciences, School of Natural Sciences, University of Limerick (UL), Limerick V94 T9PX, Ireland.
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21
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Fossat M, Zeng X, Pappu RV. Uncovering Differences in Hydration Free Energies and Structures for Model Compound Mimics of Charged Side Chains of Amino Acids. J Phys Chem B 2021; 125:4148-4161. [PMID: 33877835 PMCID: PMC8154595 DOI: 10.1021/acs.jpcb.1c01073] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/07/2021] [Indexed: 02/07/2023]
Abstract
Free energies of hydration are of fundamental interest for modeling and understanding conformational and phase equilibria of macromolecular solutes in aqueous phases. Of particular relevance to systems such as intrinsically disordered proteins are the free energies of hydration and hydration structures of model compounds that mimic charged side chains of Arg, Lys, Asp, and Glu. Here, we deploy a Thermodynamic Cycle-based Proton Dissociation (TCPD) approach in conjunction with data from direct measurements to obtain estimates for the free energies of hydration for model compounds that mimic the side chains of Arg+, Lys+, Asp-, and Glu-. Irrespective of the choice made for the hydration free energy of the proton, the TCPD approach reveals clear trends regarding the free energies of hydration for Arg+, Lys+, Asp-, and Glu-. These trends include asymmetries between the hydration free energies of acidic (Asp- and Glu-) and basic (Arg+ and Lys+) residues. Further, the TCPD analysis, which relies on a combination of experimental data, shows that the free energy of hydration of Arg+ is less favorable than that of Lys+. We sought a physical explanation for the TCPD-derived trends in free energies of hydration. To this end, we performed temperature-dependent calculations of free energies of hydration and analyzed hydration structures from simulations that use the polarizable Atomic Multipole Optimized Energetics for Biomolecular Applications (AMOEBA) force field and water model. At 298 K, the AMOEBA model generates estimates of free energies of hydration that are consistent with TCPD values with a free energy of hydration for the proton of ca. -259 kcal/mol. Analysis of temperature-dependent simulations leads to a structural explanation for the observed differences in free energies of hydration of ionizable residues and reveals that the heat capacity of hydration is positive for Arg+ and Lys+ and negative for Asp- and Glu-.
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Affiliation(s)
| | | | - Rohit V. Pappu
- Department of Biomedical Engineering
and Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, Missouri 63130, United States
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22
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Konermann L, Aliyari E, Lee JH. Mobile Protons Limit the Stability of Salt Bridges in the Gas Phase: Implications for the Structures of Electrosprayed Protein Ions. J Phys Chem B 2021; 125:3803-3814. [PMID: 33848419 DOI: 10.1021/acs.jpcb.1c00944] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Electrosprayed protein ions can retain native-like conformations. The intramolecular contacts that stabilize these compact gas-phase structures remain poorly understood. Recent work has uncovered abundant salt bridges in electrosprayed proteins. Salt bridges are zwitterionic BH+/A- contacts. The low dielectric constant in the vacuum strengthens electrostatic interactions, suggesting that salt bridges could be a key contributor to the retention of compact protein structures. A problem with this assertion is that H+ are mobile, such that H+ transfer can convert salt bridges into neutral B0/HA0 contacts. This possible salt bridge annihilation puts into question the role of zwitterionic motifs in the gas phase, and it calls for a detailed analysis of BH+/A- versus B0/HA0 interactions. Here, we investigate this issue using molecular dynamics (MD) simulations and electrospray experiments. MD data for short model peptides revealed that salt bridges with static H+ have dissociation energies around 700 kJ mol-1. The corresponding B0/HA0 contacts are 1 order of magnitude weaker. When considering the effects of mobile H+, BH+/A- bond energies were found to be between these two extremes, confirming that H+ migration can significantly weaken salt bridges. Next, we examined the protein ubiquitin under collision-induced unfolding (CIU) conditions. CIU simulations were conducted using three different MD models: (i) Positive-only runs with static H+ did not allow for salt bridge formation and produced highly expanded CIU structures. (ii) Zwitterionic runs with static H+ resulted in abundant salt bridges, culminating in much more compact CIU structures. (iii) Mobile H+ simulations allowed for the dynamic formation/annihilation of salt bridges, generating CIU structures intermediate between scenarios (i) and (ii). Our results uncover that mobile H+ limit the stabilizing effects of salt bridges in the gas phase. Failure to consider the effects of mobile H+ in MD simulations will result in unrealistic outcomes under CIU conditions.
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Affiliation(s)
- Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Elnaz Aliyari
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Justin H Lee
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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23
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Hirakawa T, Nishimoto CK, Komano A, Otsuka M, Negishi N, Miyaguchi H, Seto Y, Takeuchi K. Experimental study for adsorption and photocatalytic reaction of ethyl methylphosphonate molecule as organophosphorus compound adsorbed at surface of titanium dioxide under UV irradiation in ambient condition. RESEARCH ON CHEMICAL INTERMEDIATES 2021. [DOI: 10.1007/s11164-020-04389-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Gunasekera PS, Abhyankar PC, MacMillan SN, Lacy DC. A Facially Coordinating Tris‐Benzimidazole Ligand for Nonheme Iron Enzyme Models. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202000984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Parami S. Gunasekera
- Department of Chemistry University at Buffalo State University of New York Buffalo New York 14260 United States
| | - Preshit C. Abhyankar
- Department of Chemistry University at Buffalo State University of New York Buffalo New York 14260 United States
| | - Samantha N. MacMillan
- Department of Chemistry and Chemical Biology Cornell University Ithaca New York 14853 United States
| | - David C. Lacy
- Department of Chemistry University at Buffalo State University of New York Buffalo New York 14260 United States
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25
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Bellamy‐Carter J, O'Grady L, Passmore M, Jenner M, Oldham NJ. Decoding Protein Gas‐Phase Stability with Alanine Scanning and Collision‐Induced Unfolding Ion Mobility Mass Spectrometry. ACTA ACUST UNITED AC 2020. [DOI: 10.1002/anse.202000019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | - Louisa O'Grady
- School of Chemistry University of Nottingham University Park Nottingham NG7 2RD UK
| | - Munro Passmore
- Department of Chemistry University of Warwick Coventry CV4 7AL UK
| | - Matthew Jenner
- Department of Chemistry University of Warwick Coventry CV4 7AL UK
- Warwick Integrative Synthetic Biology Centre University of Warwick Coventry CV4 7AL UK
| | - Neil J. Oldham
- School of Chemistry University of Nottingham University Park Nottingham NG7 2RD UK
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26
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Sammut Bartolo N, Zoidis G, Gikas E, Benaki D, Ferrito V, Serracino-Inglott A. A multi-technique analytical approach for impurity profiling during synthesis: The case of difluprednate. J Pharm Biomed Anal 2020; 190:113483. [DOI: 10.1016/j.jpba.2020.113483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 11/29/2022]
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27
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Shenderovich IG. For Whom a Puddle Is the Sea? Adsorption of Organic Guests on Hydrated MCM-41 Silica. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:11383-11392. [PMID: 32900200 DOI: 10.1021/acs.langmuir.0c02327] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Thermal and hydration effects on the mobility of compact and branched organic molecules and a bulky pharmaceutical substance loaded in submonolayer amounts onto mesoporous silica have been elucidated using 1H and 31P solid-state NMR. In all cases, the ambient hydration has a stronger effect than an increase in temperature to 370 K for water-free silica. The effect of hydration depends on the guest and ranges from complete solvation to a silica-water-guest sandwich structure to a silica-guest/silica-water pattern. The mobility of the guests under different conditions has been described. The specific structure of the MCM-41 surface allows one to study very slow surface diffusion, a diffusivity of about 10-15-10-16 m2/s. The data reported are relevant to any nonfunctionalized silica, while the method used is applicable to any phosphor-containing guest on any host.
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Affiliation(s)
- Ilya G Shenderovich
- Institute of Organic Chemistry, University of Regensburg, Universitaetstrasse 31, 93053 Regensburg, Germany
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28
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Miller ZM, Zhang JD, Donald WA, Prell JS. Gas-Phase Protonation Thermodynamics of Biological Lipids: Experiment, Theory, and Implications. Anal Chem 2020; 92:10365-10374. [PMID: 32628014 DOI: 10.1021/acs.analchem.0c00613] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Phospholipids are important to cellular function and are a vital structural component of plasma and organelle membranes. These membranes isolate the cell from its environment, allow regulation of the internal concentrations of ions and small molecules, and host diverse types of membrane proteins. It remains extremely challenging to identify specific membrane protein-lipid interactions and their relative strengths. Native mass spectrometry, an intrinsically gas-phase method, has recently been demonstrated as a promising tool for identifying endogenous protein-lipid interactions. However, to what extent the identified interactions reflect solution- versus gas-phase binding strengths is not known. Here, the "Extended" Kinetic Method and ab initio computations at three different levels of theory are used to experimentally and theoretically determine intrinsic gas-phase basicities (GB, ΔG for deprotonation of the protonated base) and proton affinities (PA, ΔH for deprotonation of the protonated base) of six lipids representing common phospholipid types. Gas-phase acidities (ΔG and ΔH for deprotonation) of neutral phospholipids are also evaluated computationally and ranked experimentally. Intriguingly, it is found that two of these phospholipids, sphingomyelin and phosphatidylcholine, have the highest GB of any small, monomeric biomolecules measured to date and are more basic than arginine. Phosphatidylethanolamine and phosphatidylserine are found to be similar in GB to basic amino acids lysine and histidine, and phosphatidic acid and phosphatidylglycerol are the least basic of the six lipid types studied, though still more basic than alanine. Kinetic Method experiments and theory show that the gas-phase acidities of these phospholipids are high but less extreme than their GB values, with phosphatidylserine and phosphatidylglycerol being the most acidic. These results indicate that sphingomyelin and phosphatidylcholine lipids can act as charge-reducing agents when dissociated from native membrane protein-lipid complexes in the gas phase and provide a straightforward model to explain the results of several recent native mass spectrometry studies of protein-lipid complexes.
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Affiliation(s)
- Zachary M Miller
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403-1253, United States
| | - J Diana Zhang
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia, 2052
| | - W Alexander Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia, 2052
| | - James S Prell
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403-1253, United States.,Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1252, United States
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29
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Sever AIM, Konermann L. Gas Phase Protein Folding Triggered by Proton Stripping Generates Inside-Out Structures: A Molecular Dynamics Simulation Study. J Phys Chem B 2020; 124:3667-3677. [DOI: 10.1021/acs.jpcb.0c01934] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Alexander I. M. Sever
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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30
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Haack A, Polaczek C, Tsolakis M, Thinius M, Kersten H, Benter T. Charge Retention/Charge Depletion in ESI-MS: Theoretical Rationale. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:785-795. [PMID: 32150409 DOI: 10.1021/jasms.9b00045] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Gas phase modification in ESI-MS can significantly alter the charge state distribution of small peptides and proteins. The preceding paper presented a systematic experimental study on this topic using Substance P and proposed a charge retention/charge depletion mechanism, explaining different gas- and liquid-phase modifications [Thinius et al. J. Am. Soc. Mass Spec. 2020, 10.1021/jasms.9b00044]. In this work, we aim to support this rational by theoretical investigations on the proton transfer processes from (multiply) charged analytes toward solvent clusters. As model systems we use small (di)amines as analytes and methanol (MeOH) and acetonitrile (ACN) as gas phase modifiers. The calculations are supported by a set of experiments using (di)amines, to bridge the gap between the present model system and Substance P used in the preceding study. Upon calculation of the thermochemical stability as well as the proton transfer pathways, we find that both ACN and MeOH form stable adduct clusters at the protonation site. MeOH can form large clusters through a chain of H-bridges, eventually lowering the barriers for proton transfer to an extent that charge transfer from the analyte to the MeOH cluster becomes feasible. ACN, however, cannot form H-bridged structures due to its aprotic nature. Hence, the charge is retained at the original protonation site, i.e., the analyte. The investigation confirms the proposed charge retention/charge depletion model. Thus, adding aprotic solvent vapors to the gas phase of an ESI source more likely yields higher charge states than using protic compounds.
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Affiliation(s)
- Alexander Haack
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Christine Polaczek
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Manuel Tsolakis
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Marco Thinius
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Hendrik Kersten
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Thorsten Benter
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
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31
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Thinius M, Polaczek C, Langner M, Bräkling S, Haack A, Kersten H, Benter T. Charge Retention/Charge Depletion in ESI-MS: Experimental Evidence. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:773-784. [PMID: 32150403 DOI: 10.1021/jasms.9b00044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The effects of liquid and gas phase additives (chemical modifiers) on the ion signal distribution for Substance P (SP), recorded with a nanoelectrospray setup, are evaluated. Depletion of the higher charge state of Substance P ([SP+3H]3+) is observed with polar protic gas phase modifiers. This is attributed to their ability to form larger hydrogen-bonded clusters, whose proton affinity increases with cluster size. These clusters are able to deprotonate the higher charge state. "Supercharging agents" (SCAs) as well as aprotic polar gas phase modifiers, which promote the retention of the higher charge state of Substance P, do not form such large clusters under the given conditions and are therefore not able to deprotonate Substance P. Both SCAs and aprotic modifiers form clusters with the higher charge state, leading to stabilization of the charge. Whereas supercharging agents have low vapor pressures and are therefore enriched in late-stage electrospray droplets, the gas phase modifiers are volatile organic solvents. Collision induced dissociation experiments revealed that the addition of a modifier significantly delays the droplet evaporation and ion release process. This indicates that the droplet takes up the gas phase modifier to a certain extent (accommodation). Depending on the modifier's properties either charge depletion or retention may eventually be promoted.
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Affiliation(s)
- Marco Thinius
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Christine Polaczek
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Markus Langner
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Steffen Bräkling
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Alexander Haack
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Hendrik Kersten
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
| | - Thorsten Benter
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Gauss Str. 20, 42119 Wuppertal, Germany
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32
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von Rudorff GF, von Lilienfeld OA. Rapid and accurate molecular deprotonation energies from quantum alchemy. Phys Chem Chem Phys 2020; 22:10519-10525. [PMID: 31960870 DOI: 10.1039/c9cp06471k] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We assess the applicability of alchemical perturbation density functional theory (APDFT) for quickly and accurately estimating deprotonation energies. We have considered all possible single and double deprotonations in one hundred small organic molecules drawn at random from QM9 [Ramakrishnan et al., JCTC, 2015]. Numerical evidence is presented for 5160 deprotonated species at both HF/def2-TZVP and CCSD/6-31G* levels of theory. We show that the perturbation expansion formalism of APDFT quickly converges to reliable results: using CCSD electron densities and derivatives, regular Hartree-Fock calculations are outperformed at the second or third order for ranking all possible doubly or singly deprotonated molecules, respectively. CCSD single deprotonation energies are reproduced within 1.4 kcal mol-1 on average within third order APDFT. We introduce a hybrid approach where the computational cost of APDFT is reduced even further by mixing first order terms at a higher level of theory (CCSD) with higher order terms at a lower level of theory only (HF). We find that this approach reaches 2 kcal mol-1 accuracy in absolute deprotonation energies compared to CCSD at 2% of the computational cost of third order APDFT.
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Affiliation(s)
- Guido Falk von Rudorff
- Institute of Physical Chemistry and National Center for Computational Design and Discovery of Novel Materials (MARVEL), Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
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33
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Shenderovich IG, Denisov GS. Adduct under Field-A Qualitative Approach to Account for Solvent Effect on Hydrogen Bonding. Molecules 2020; 25:molecules25030436. [PMID: 31973045 PMCID: PMC7037398 DOI: 10.3390/molecules25030436] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 02/08/2023] Open
Abstract
The location of a mobile proton in acid-base complexes in aprotic solvents can be predicted using a simplified Adduct under Field (AuF) approach, where solute–solvent effects on the geometry of hydrogen bond are simulated using a fictitious external electric field. The parameters of the field have been estimated using experimental data on acid-base complexes in CDF3/CDClF2. With some limitations, they can be applied to the chemically similar CHCl3 and CH2Cl2. The obtained data indicate that the solute–solvent effects are critically important regardless of the type of complexes. The temperature dependences of the strength and fluctuation rate of the field explain the behavior of experimentally measured parameters.
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Affiliation(s)
- Ilya G. Shenderovich
- Institute of Organic Chemistry, University of Regensburg, Universitaetstrasse 31, 93053 Regensburg, Germany
- Correspondence: ; Tel.:+49-941-9434027
| | - Gleb S. Denisov
- Department of Physics, Saint-Petersburg State University, 198504 Saint-Petersburg, Russia;
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34
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Cao X, Wu L, Zhang J, Dolg M. Density Functional Studies of Coenzyme NADPH and Its Oxidized Form NADP + : Structures, UV-Vis Spectra, and the Oxidation Mechanism of NADPH. J Comput Chem 2019; 41:305-316. [PMID: 31713255 DOI: 10.1002/jcc.26103] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/03/2019] [Accepted: 10/16/2019] [Indexed: 12/31/2022]
Abstract
Density functional theory has been used to study the biologically important coenzyme NADPH and its oxidized form NADP+ . It was found that free NADPH prefers a compact structure in gas phase and exists in more extended geometries in aqueous solution. Ultraviolet-visible absorption spectra in aqueous solution were calculated for NADPH with an explicit treatment of 100 surrounding water molecules in combination with the COSMO solvation model for bulk hydration effects. The obtained spectra using the B3LYP hybrid density functional agree quite well with experimental data. The changes of Gibbs free energies ΔG in reactions of NADPH with O2 observed experimentally in cardiovascular and in chemical systems, that is, NADPH + 2 3 O2 → NADP+ + 2 O2 - + H+ and NADPH + 1 O2 + H+ → NADP+ + H2 O2 , respectively, were calculated. The NADPH oxidation reaction in the cardiovascular system cannot proceed without activation since the obtained ΔG is positive. The reaction of NADPH in the chemical system with singlet oxygen was found to proceed in two ways, each consisting of two steps, that is, NADPH firstly reacts with 1 O2 barrierlessly to form NADP+ and HO2 - , from which H2 O2 is formed in a spontaneous reaction with H+ , or 1 O2 and H+ initially form 1 HO2 + , which further reacts with NADPH to yield NADP+ and H2 O2 . © 2019 The Authors. Journal of Computational Chemistry published by Wiley Periodicals, Inc.
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Affiliation(s)
- Xiaoyan Cao
- Institute for Theoretical Chemistry, University of Cologne, Greinstr. 4, D-50939, Cologne, Germany
| | - Liangliang Wu
- Institute for Theoretical Chemistry, University of Cologne, Greinstr. 4, D-50939, Cologne, Germany.,Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education, Department of Chemistry, Beijing Normal University, Xin-wai-da-jie No. 19, Beijing, 10087, China
| | - Jun Zhang
- Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, Illinois, 61801-3364
| | - Michael Dolg
- Institute for Theoretical Chemistry, University of Cologne, Greinstr. 4, D-50939, Cologne, Germany
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35
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Boughlala Z, Fonseca Guerra C, Bickelhaupt FM. Alkali Metal Cation Affinities of Neutral Maingroup-Element Hydrides across the Periodic Table. J Phys Chem A 2019; 123:9137-9148. [PMID: 31294982 PMCID: PMC6816011 DOI: 10.1021/acs.jpca.9b03814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
We have carried out
an extensive quantum chemical exploration of
gas-phase alkali metal cation affinities (AMCAs) of archetypal neutral
bases across the periodic system using relativistic density functional
theory. One objective of this work is to provide an intrinsically
consistent set of values of the 298 K AMCAs of all neutral maingroup-element
hydrides XHn of groups 15–18 along
the periods 1–6. Our main purpose is to understand these trends
in terms of the underlying bonding mechanism using Kohn–Sham
molecular orbital theory together with a canonical energy decomposition
analysis (EDA). We compare the trends in XHn AMCAs with the trends in XHn proton
affinities (PAs). We also examine the differences between the trends
in AMCAs of the neutral XHn bases with
those in the corresponding anionic XHn–1– bases. Furthermore, we analyze how the cation
affinity of our neutral Lewis bases changes along the group-1 cations
H+, Li+, Na+, K+, Rb+, and Cs+.
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Affiliation(s)
- Zakaria Boughlala
- Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM) , Vrije Universiteit Amsterdam , De Boelelaan 1083 , NL-1081 HV Amsterdam , The Netherlands
| | - Célia Fonseca Guerra
- Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM) , Vrije Universiteit Amsterdam , De Boelelaan 1083 , NL-1081 HV Amsterdam , The Netherlands.,Leiden Institute of Chemistry , Leiden University , PO Box 9502, NL-2300 RA Leiden , The Netherlands
| | - F Matthias Bickelhaupt
- Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling (ACMM) , Vrije Universiteit Amsterdam , De Boelelaan 1083 , NL-1081 HV Amsterdam , The Netherlands.,Institute of Molecules and Materials , Radboud University , Heyendaalseweg 135 , NL-6525 AJ Nijmegen , The Netherlands
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36
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On the Use of Popular Basis Sets: Impact of the Intramolecular Basis Set Superposition Error. Molecules 2019; 24:molecules24203810. [PMID: 31652663 PMCID: PMC6832644 DOI: 10.3390/molecules24203810] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 10/16/2019] [Accepted: 10/18/2019] [Indexed: 11/16/2022] Open
Abstract
The magnitude of intramolecular basis set superposition error (BSSE) is revealed via computing systematic trends in molecular properties. This type of error is largely neglected in the study of the chemical properties of small molecules and it has historically been analyzed just in the study of large molecules and processes dominated by non-covalent interactions (typically dimerization or molecular complexation and recognition events). In this work we try to provide proof of the broader prevalence of this error, which permeates all types of electronic structure calculations, particularly when employing insufficiently large basis sets.
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37
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Shin J. Extended kinetic method study of the effect of
ortho
‐,
meta
‐, and
para
‐chlorination on the proton affinity of phenylalanine with full entropy analysis. J PHYS ORG CHEM 2019. [DOI: 10.1002/poc.3966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Joong‐Won Shin
- Division of Science, Mathematics, and TechnologyGovernors State University University Park IL USA
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38
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De Vylder A, Lauwaert J, Sabbe MK, Reyniers MF, De Clercq J, Van Der Voort P, Thybaut JW. Rational design of nucleophilic amine sites via computational probing of steric and electronic effects. Catal Today 2019. [DOI: 10.1016/j.cattod.2019.01.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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39
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Ridley MK, Lischka H, Tunega D, Aquino AJ. Solvent effect on Al(III) hydrolysis constants from density functional theory. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1567846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Moira K. Ridley
- Department of Geosciences, Texas Tech University, Lubbock, USA
| | - Hans Lischka
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, People's Republic of China
- Institute of Theoretical Chemistry, University of Vienna, Vienna, Austria
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, USA
| | - Daniel Tunega
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, People's Republic of China
- Institute for Soil Research, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Adelia J.A. Aquino
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, People's Republic of China
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, USA
- Institute for Soil Research, University of Natural Resources and Life Sciences, Vienna, Austria
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40
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Peters I, Metwally H, Konermann L. Mechanism of Electrospray Supercharging for Unfolded Proteins: Solvent-Mediated Stabilization of Protonated Sites During Chain Ejection. Anal Chem 2019; 91:6943-6952. [DOI: 10.1021/acs.analchem.9b01470] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Insa Peters
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Haidy Metwally
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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41
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Park JJ, Han SY. Alternated Branching Ratios by Anomaly in Collision-Induced Dissociation of Proton-Bound Hoogsteen Base Pairs of 1-Methylcytosine with 1-Methylguanine and 9-Methylguanine. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:846-854. [PMID: 30911905 DOI: 10.1007/s13361-019-02161-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 01/26/2019] [Accepted: 02/14/2019] [Indexed: 06/09/2023]
Abstract
A comparative study on the proton-bound complexes of 1-methylcytosine (1-mC) with 1-methylguanine (1-mG) and 9-methylguanine (9-mG), [1-mC:1-mG:H]+ and [1-mC:9-mG:H]+, respectively, was carried out using energy-resolved collision-induced dissociation (ER-CID) experiments in combination with quantum chemical calculations. In ER-CID experiments, the measured survival yields indicated an essentially identical stability for the two proton-bound complexes. In comparison with the lowest-energy structures and base-pairing energetics predicted at the B3LYP/6-311+G(2d,2p) theory level, both complexes produced in this study were suggested to be proton-bound Hoogsteen base pairs. Curiously, despite the similarity in structures, binding energetics, and potential energy surfaces predicted by the B3LYP theory, the fragment branching ratios exhibited an intriguing alternation between the two proton-bound Hoogsteen base pairs. The CID of [1-mC:1-mG:H]+ produced protonated cytosines, [1-mC:H]+, more abundantly than [1-mG:H]+, whereas that of [1-mC:9-mG:H]+ gave rise to a more pronounced production of protonated guanines, [9-mG:H]+. However, using the proton affinities of moieties predicted by the high-accuracy methods, including CBS-QB3 and the Guassian-4 theory, the anomaly known for [Cytosine:Guanine:H]+ (J. Am. Soc. Mass Spectrom. 29, 2368-2379 (2018)) successfully accounted for the alternated branching ratios. Thereby, the anomaly, more specifically, the production of proton-transferred fragments of O-protonated cytosines in the CID of proton-bound Hoogsteen base pairs, is indeed real, which is disclosed as the alternated branching ratios in the CID spectra of [1-mC:1-mG:H]+ and [1-mC:9-mG:H]+ in this study. Graphical Abstract .
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Affiliation(s)
- Jeong Ju Park
- Department of Nanochemistry, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do, 13120, Republic of Korea
| | - Sang Yun Han
- Department of Nanochemistry, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do, 13120, Republic of Korea.
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42
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Zobeydi R, Nazari P, Rahman Setayesh S. Theoretical study of the thermodynamic parameters of (CaO)n nanoclusters with n = 2–16 in the gas and solution phases: proton affinity, molecular basicity, and pKb values. Struct Chem 2019. [DOI: 10.1007/s11224-019-01318-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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43
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Vrána J, Holub J, Samsonov MA, RůŽičková Z, Fanfrlík J, Hnyk D, RůŽička A. Thiaborane clusters with an exoskeletal B-H group. Chem Commun (Camb) 2019; 55:3375-3378. [PMID: 30816893 DOI: 10.1039/c9cc00952c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The thiaboranes closo-1-SB11H11 (1a) and 12-I-closo-1-SB11H10 (1b) react with 4-(dimethylamino)pyridine under inert conditions upon the formation of the nido-type thiaboranes 9-B{(4-Me2N)C5NH4}2(H)-7-SB10H11 and 9-B{(4-Me2N)C5NH4}2(H)-5-I-7-SB10H10 containing an exoskeletal B-H group. The same type of B-H moiety is also stabilised by one bipyridine molecule in a chelating fashion. These complexes are unstable in solution, and in air and hydrolyse to monodeboronated ionic compounds having [nido-7-SB10H11]- or [5-I-nido-7-SB10H10]- anions which are also products of the reactions of 1a and 1b with other N-bases such as pyridine, ammonia and DABCO. The extrusion of one boron and one sulphur atom takes place when 1a reacts with 2,6-di-tert-butylpyridine to yield decaborane.
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Affiliation(s)
- Jan Vrána
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Pardubice, Studentská 573, CZ-532 10, Czech Republic.
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44
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Beshara C, Shustov G. Inside-protonated 1-azaadamantane: computational studies on the structure, stability, and generation. CAN J CHEM 2019. [DOI: 10.1139/cjc-2018-0407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Post Hartree–Fock and density functional theory methods have been employed to study inside-protonated 1-azaadamantane 7 and its complexes with the fluoride counterion (contact ion pairs) 10 and 11. The study also involved 1-azaadamantane 4, its outside-protonated form 8, and 1-azaadamantane radical cation 17. Inside-protonated 1-azaadamantane 7 is more than 82 kcal mol−1less stable than out-isomer 8. The repulsive interaction between the internal N+–H group and the azaadamantane cage and a substantial deformation of this cage greatly weaken the C–N and C–C bonds and, consequently, lead to a low kinetic stability of in-ion 7 in the studied unimolecular and bimolecular reactions involving the removal of the encapsulated proton from the cage. Among these reactions, a 7 → 8 rearrangement through a reversible cage opening at the C–N bond was found to be the main transformation channel ([Formula: see text] < 16 kcal mol−1) for in-ion 7. This rearrangement can be catalyzed by an external base, e.g., the fluoride anion. A 1,4-hydrogen migration in 1-azaadamantane radical cation 17 as a possible pathway to the inside-protonated 1-azaadamantane 7 was explored. It was found that this process has a prohibitively high activation barrier, [Formula: see text] > 104 kcal mol−1, and is not able to compete with the α-C–C cleavage of the azaadamantane cage ([Formula: see text] < 26 kcal mol−1).
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Affiliation(s)
- Cory Beshara
- Department of Chemistry, University College of the Fraser Valley, Abbotsford, BC V2S 7M8, Canada
- Department of Chemistry, University College of the Fraser Valley, Abbotsford, BC V2S 7M8, Canada
| | - Gennady Shustov
- Department of Chemistry, University College of the Fraser Valley, Abbotsford, BC V2S 7M8, Canada
- Department of Chemistry, University College of the Fraser Valley, Abbotsford, BC V2S 7M8, Canada
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45
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Wang P, Liang G, Boyd CL, Webster CE, Zhao X. Catalytic H
2
Evolution by a Mononuclear Cobalt Complex with a Macrocyclic Pentadentate Ligand. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201801418] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Ping Wang
- Department of Chemistry The University of Memphis Memphis Tennessee 38152 USA
| | - Guangchao Liang
- Department of Chemistry Mississippi State University Mississippi 39762 USA
| | | | | | - Xuan Zhao
- Department of Chemistry The University of Memphis Memphis Tennessee 38152 USA
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46
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Bakhtiari M, Konermann L. Protein Ions Generated by Native Electrospray Ionization: Comparison of Gas Phase, Solution, and Crystal Structures. J Phys Chem B 2019; 123:1784-1796. [DOI: 10.1021/acs.jpcb.8b12173] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Maryam Bakhtiari
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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47
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Devereaux ZJ, Zhu Y, Rodgers MT. Relative glycosidic bond stabilities of naturally occurring methylguanosines: 7-methylation is intrinsically activating. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2019; 25:16-29. [PMID: 30189754 DOI: 10.1177/1469066718798097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The frequency and diversity of posttranscriptional modifications add an additional layer of chemical complexity beyond canonical nucleic acid sequence. Methylations are particularly frequently occurring and often highly conserved throughout the kingdoms of life. However, the intricate functions of these modified nucleic acid constituents are often not fully understood. Systematic foundational research that reduces systems to their minimum constituents may aid in unraveling the complexities of nucleic acid biochemistry. Here, we examine the relative intrinsic N-glycosidic bond stabilities of guanosine and five naturally occurring methylguanosines (O2'-, 1-, 7-, N2,N2-di-, and N2,N2,O2'-trimethylguanosine) probed by energy-resolved collision-induced dissociation tandem mass spectrometry and complemented with quantum chemical calculations. Apparent glycosidic bond stability is generally found to increase with increasing methyl substitution (canonical < mono- < di- < trimethylated). Many biochemical transformations, including base excision repair mechanisms, involve protonation and/or noncovalent interactions to increase nucleobase leaving-group ability. The protonated gas-phase methylguanosines require less activation energy for glycosidic bond cleavage than their sodium cationized forms. However, methylation at the N7 position intrinsically weakens the glycosidic bond of 7-methylguanosine more significantly than subsequent cationization, and thus 7-methylguanosine is suggested to be under perpetually activated conditions. N7 methylation also alters the nucleoside geometric preferences relative to the other systems, including the nucleobase orientation in the neutral form, sugar puckering in the protonated form, and the preferred protonation and sodium cation binding sites. All of the methylated guanosines examined here are predicted to have proton affinities and gas-phase basicities that exceed that of canonical guanosine. Additionally, the proton affinity and gas-phase basicity trends exhibit a roughly inverse correlation with the apparent glycosidic bond stabilities.
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Affiliation(s)
| | - Y Zhu
- Department of Chemistry, Wayne State University, Detroit, USA
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, USA
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48
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Ghalami-Choobar B, Ghiami-Shomami A, Fereidoonzadeh M. Relative p K
a
of some anilinium derivatives in methanol, acetonitrile, and tetrahydrofurane solvents. J CHIN CHEM SOC-TAIP 2019. [DOI: 10.1002/jccs.201800139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - Ali Ghiami-Shomami
- Department of Chemistry, Faculty of Science; University of Guilan; Rasht Iran
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49
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Pandeti S, Feketeová L, Reddy TJ, Abdoul-Carime H, Farizon B, Farizon M, Märk TD. Binding preference of nitroimidazolic radiosensitizers to nucleobases and nucleosides probed by electrospray ionization mass spectrometry and density functional theory. J Chem Phys 2019; 150:014302. [PMID: 30621427 DOI: 10.1063/1.5062604] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Nitroimidazolic radiosensitizers are used in radiation therapy to selectively sensitize cancer cells deprived of oxygen, and the actual mechanism of radiosensitization is still not understood. Selecting five radiosensitizers (1-methyl-5-nitroimidazole, ronidazole, ornidazole, metronidazole, and nimorazole) with a common 5-nitroimidazolic ring with different substitutions at N1 and C2 positions of the imidazole moiety, we investigate here their binding to nucleobases (A, T, G, and C) and nucleosides (As, Td, Gs, and Cd) via the positive electrospray ionization mass spectrometry experiments. In addition, quantum chemical calculations at the M062x/6-311+G(d,p) level of theory and basis set were used to determine binding energies of the proton bound dimers of a radiosensitizer and a nucleobase. The positive electrospray ionization leads to the formation of proton bound dimers of all radiosensitizers except 1-methyl-5-nitroimidazole in high abundance with C and smaller abundance with G. Ronidazole and metronidazole formed less abundant dimers also with A, while no dimers were observed to be formed at all with T. In contrast to the case of the nucleoside Td, the dimer intensity is as high as that with Cd, while the abundance of the dimer with Gs is smaller than that of the former. The experimental results are consistent with the calculations of binding energies suggesting proton bound dimers with C and G to be the strongest bound ones. Finally, a barrier-free proton transfer is observed when protonated G or C approaches the nitroimidazole ring.
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Affiliation(s)
- S Pandeti
- Université de Lyon, Université Claude Bernard Lyon1, Institut de Physique Nucléaire de Lyon, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne Cedex, France
| | - L Feketeová
- Université de Lyon, Université Claude Bernard Lyon1, Institut de Physique Nucléaire de Lyon, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne Cedex, France
| | - T J Reddy
- Analytical Chemistry and Mass Spectrometry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India
| | - H Abdoul-Carime
- Université de Lyon, Université Claude Bernard Lyon1, Institut de Physique Nucléaire de Lyon, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne Cedex, France
| | - B Farizon
- Université de Lyon, Université Claude Bernard Lyon1, Institut de Physique Nucléaire de Lyon, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne Cedex, France
| | - M Farizon
- Université de Lyon, Université Claude Bernard Lyon1, Institut de Physique Nucléaire de Lyon, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne Cedex, France
| | - T D Märk
- Institut für Ionenphysik und Angewandte Physik, Leopold Franzens Universität Innsbruck, Technikerstrasse 25, 6020 Innsbruck, Austria
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50
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Hydride affinities of cationic maingroup-element hydrides across the periodic table. RESULTS IN CHEMISTRY 2019. [DOI: 10.1016/j.rechem.2019.100007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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