1
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Xue K, Nimerovsky E, Tekwani Movellan KA, Becker S, Andreas LB. Backbone Torsion Angle Determination Using Proton Detected Magic-Angle Spinning Nuclear Magnetic Resonance. J Phys Chem Lett 2022; 13:18-24. [PMID: 34957837 PMCID: PMC8762656 DOI: 10.1021/acs.jpclett.1c03267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
Protein torsion angles define the backbone secondary structure of proteins. Magic-angle spinning (MAS) NMR methods using carbon detection have been developed to measure torsion angles by determining the relative orientation between two anisotropic interactions─dipolar coupling or chemical shift anisotropy. Here we report a new proton-detection based method to determine the backbone torsion angle by recoupling NH and CH dipolar couplings within the HCANH pulse sequence, for protonated or partly deuterated samples. We demonstrate the efficiency and precision of the method with microcrystalline chicken α spectrin SH3 protein and the influenza A matrix 2 (M2) membrane protein, using 55 or 90 kHz MAS. For M2, pseudo-4D data detect a turn between transmembrane and amphipathic helices.
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2
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Gong Y, Zhan C, Zou Y, Qian Z, Wei G, Zhang Q. Serotonin and Melatonin Show Different Modes of Action on Aβ 42 Protofibril Destabilization. ACS Chem Neurosci 2021; 12:799-809. [PMID: 33533252 DOI: 10.1021/acschemneuro.1c00038] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Alzheimer's disease (AD) is associated with the aberrant self-assembly of amyloid-β (Aβ) protein into fibrillar deposits. The disaggregation of Aβ fibril is believed as one of the major therapeutic strategies for treating AD. Previous experimental studies reported that serotonin (Ser), one of the indoleamine neurotransmitters, and its derivative melatonin (Mel) are able to disassemble preformed Aβ fibrils. However, the fibril-disruption mechanisms are unclear. As the first step to understand the underlying mechanism, we investigated the interactions of Ser and Mel molecules with the LS-shaped Aβ42 protofibril by performing a total of nine individual 500 ns all-atom molecular dynamics (MD) simulations. The simulations demonstrate that both Ser and Mel molecules disrupt the local β-sheet structure, destroy the salt bridges between K28 side chain and A42 COO-, and consequently destabilize the global structure of Aβ42 protofibril. The Mel molecule exhibits a greater binding capacity than the Ser molecule. Intriguingly, we find that Ser and Mel molecules destabilize Aβ42 protofibril through different modes of action. Ser preferentially binds with the aromatic residues in the N-terminal region through π-π stacking interactions, while Mel binds not only with the N-terminal aromatic residues but also with the C-terminal hydrophobic residues via π-π and hydrophobic interactions. This work reveals the disruptive mechanisms of Aβ42 protofibril by Ser and Mel molecules and provides useful information for designing drug candidates against AD.
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Affiliation(s)
- Yehong Gong
- College of Physical Education and Training, Shanghai University of Sport, 399 Chang Hai Road, Shanghai 200438, People’s Republic of China
| | - Chendi Zhan
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Sciences (Ministry of Education), Fudan University, Shanghai 200438, People’s Republic of China
| | - Yu Zou
- Department Sport and Exercise Science, College of Education, Zhejiang University, 148 Tianmenshan Road, Hangzhou, 310007 Zhejiang People’s Republic of China
| | - Zhenyu Qian
- Key Laboratory of Exercise and Health Sciences (Ministry of Education) and School of Kinesiology, Shanghai University of Sport, 399 Chang Hai Road, Shanghai 200438, People’s Republic of China
| | - Guanghong Wei
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory for Computational Physical Sciences (Ministry of Education), Fudan University, Shanghai 200438, People’s Republic of China
| | - Qingwen Zhang
- College of Physical Education and Training, Shanghai University of Sport, 399 Chang Hai Road, Shanghai 200438, People’s Republic of China
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3
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Saini R, Shuaib S, Goyal D, Goyal B. Impact of Mutations on the Conformational Transition from α-Helix to β-Sheet Structures in Arctic-Type Aβ 40: Insights from Molecular Dynamics Simulations. ACS OMEGA 2020; 5:23219-23228. [PMID: 32954172 PMCID: PMC7495726 DOI: 10.1021/acsomega.0c02983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 08/13/2020] [Indexed: 05/13/2023]
Abstract
The amyloid-β (Aβ) protein aggregation into toxic oligomers and fibrils has been recognized as a key player in the pathogenesis of Alzheimer's disease. Recent experiments reported that a double alanine mutation (L17A/F19A) in the central hydrophobic core (CHC) region of [G22]Aβ40 (familial Arctic mutation) diminished the self-assembly propensity of [G22]Aβ40. However, the molecular mechanism behind the decreased aggregation tendency of [A17/A19/G22]Aβ40 is not well understood. Herein, we carried out molecular dynamics simulations to elucidate the structure and dynamics of [G22]Aβ40 and [A17/A19/G22]Aβ40. The results for the secondary structure analysis reveal a significantly increased amount of the helical content in the CHC and C-terminal region of [A17/A19/G22]Aβ40 as compared to [G22]Aβ40. The bending free-energy analysis of D23-K28 salt bridge suggests that the double alanine mutation in the CHC region of [G22]Aβ40 has the potential to reduce the fibril formation rate by 0.57 times of [G22]Aβ40. Unlike [G22]Aβ40, [A17/A19/G22]Aβ40 largely sampled helical conformation, as determined by the minimum energy conformations extracted from the free-energy landscape. The present study provided atomic level details into the experimentally observed diminished aggregation tendency of [A17/A19/G22]Aβ40 as compared to [G22]Aβ40.
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Affiliation(s)
- Rajneet
Kaur Saini
- Department
of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib 140406, Punjab, India
| | - Suniba Shuaib
- Department
of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib 140406, Punjab, India
| | - Deepti Goyal
- Department
of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib 140406, Punjab, India
| | - Bhupesh Goyal
- School
of Chemistry & Biochemistry, Thapar
Institute of Engineering & Technology, Patiala 147004, Punjab, India
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4
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Kaur A, Kaur A, Goyal D, Goyal B. How Does the Mono-Triazole Derivative Modulate Aβ 42 Aggregation and Disrupt a Protofibril Structure: Insights from Molecular Dynamics Simulations. ACS OMEGA 2020; 5:15606-15619. [PMID: 32637837 PMCID: PMC7331201 DOI: 10.1021/acsomega.0c01825] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/08/2020] [Indexed: 05/31/2023]
Abstract
Clinical studies have identified that abnormal self-assembly of amyloid-β (Aβ) peptide into toxic fibrillar aggregates is associated with the pathology of Alzheimer's disease (AD). The most acceptable therapeutic approach to stop the progression of AD is to inhibit the formation of β-sheet-rich structures. Recently, we designed and evaluated a series of novel mono-triazole derivatives 4(a-x), where compound 4v was identified as the most potent inhibitor of Aβ42 aggregation and disaggregates preformed Aβ42 fibrils significantly. Moreover, 4v strongly averts the Cu2+-induced Aβ42 aggregation and disaggregates the preformed Cu2+-induced Aβ42 fibrils, halts the generation of reactive oxygen species, and shows neuroprotective effects in SH-SY5Y cells. However, the underlying molecular mechanism of inhibition of Aβ42 aggregation by 4v and disaggregation of preformed Aβ42 fibrils remains obscure. In this work, molecular dynamics (MD) simulations have been performed to explore the conformational ensemble of the Aβ42 monomer and a pentameric protofibril structure of Aβ42 in the presence of 4v. The MD simulations highlighted that 4v binds preferentially at the central hydrophobic core region of the Aβ42 monomer and chains D and E of the Aβ42 protofibril. The dictionary of secondary structure of proteins analysis indicated that 4v retards the conformational conversion of the helix-rich structure of the Aβ42 monomer into the aggregation-prone β-sheet conformation. The binding free energy calculated by the molecular mechanics Poisson-Boltzmann surface area method revealed an energetically favorable process with ΔG binding = -44.9 ± 3.3 kcal/mol for the Aβ42 monomer-4v complex. The free energy landscape analysis highlighted that the Aβ42 monomer-4v complex sampled conformations with significantly higher helical contents (35 and 49%) as compared to the Aβ42 monomer alone (17%). Compound 4v displayed hydrogen bonding with Gly37 (chain E) and π-π interactions with Phe19 (chain D) of the Aβ42 protofibril. Further, the per-residue binding free energy analysis also highlighted that Phe19 (chain D) and Gly37 (chain E) of the Aβ42 protofibril showed the maximum contribution in the binding free energy. The decreased binding affinity and residue-residue contacts between chains D and E of the Aβ42 protofibril in the presence of 4v indicate destabilization of the Aβ42 protofibril structure. Overall, the structural information obtained through MD simulations indicated that 4v stabilizes the native helical conformation of the Aβ42 monomer and persuades a destabilization in the protofibril structure of Aβ42. The results of the study will be useful in the rational design of potent inhibitors against amyloid aggregation.
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Affiliation(s)
- Amandeep Kaur
- Department
of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib 140406, Punjab, India
| | - Anupamjeet Kaur
- Department
of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib 140406, Punjab, India
| | - Deepti Goyal
- Department
of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib 140406, Punjab, India
| | - Bhupesh Goyal
- School
of Chemistry & Biochemistry, Thapar
Institute of Engineering & Technology, Patiala 147004, Punjab, India
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5
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Shuaib S, Narang SS, Goyal D, Goyal B. Computational design and evaluation of β‐sheet breaker peptides for destabilizing Alzheimer's amyloid‐β
42
protofibrils. J Cell Biochem 2019; 120:17935-17950. [DOI: 10.1002/jcb.29061] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 04/20/2019] [Accepted: 04/29/2019] [Indexed: 12/19/2022]
Affiliation(s)
- Suniba Shuaib
- Department of Chemistry, Faculty of Basic and Applied Sciences Sri Guru Granth Sahib World University Fatehgarh Sahib India
| | - Simranjeet Singh Narang
- Department of Chemistry, Faculty of Basic and Applied Sciences Sri Guru Granth Sahib World University Fatehgarh Sahib India
| | - Deepti Goyal
- Department of Chemistry, Faculty of Basic and Applied Sciences Sri Guru Granth Sahib World University Fatehgarh Sahib India
| | - Bhupesh Goyal
- School of Chemistry & Biochemistry Thapar Institute of Engineering & Technology Patiala India
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6
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Shuaib S, Saini RK, Goyal D, Goyal B. Impact of K16A and K28A mutation on the structure and dynamics of amyloid-β42 peptide in Alzheimer’s disease: key insights from molecular dynamics simulations. J Biomol Struct Dyn 2019; 38:708-721. [DOI: 10.1080/07391102.2019.1586587] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Suniba Shuaib
- Department of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib, Punjab, India
| | - Rajneet Kaur Saini
- Department of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib, Punjab, India
| | - Deepti Goyal
- Department of Chemistry, Faculty of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib, Punjab, India
| | - Bhupesh Goyal
- School of Chemistry & Biochemistry, Thapar Institute of Engineering & Technology, Patiala, Punjab, India
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7
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Saini RK, Shuaib S, Goyal D, Goyal B. Molecular insights into the effect L17A/F19A double mutation on the structure and dynamics of Aβ
40
: A molecular dynamics simulation study. J Cell Biochem 2018; 119:8949-8961. [DOI: 10.1002/jcb.27149] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 05/18/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Rajneet Kaur Saini
- Department of Chemistry, Faculty of Basic and Applied Sciences Sri Guru Granth Sahib World University Fatehgarh Sahib India
| | - Suniba Shuaib
- Department of Chemistry, Faculty of Basic and Applied Sciences Sri Guru Granth Sahib World University Fatehgarh Sahib India
| | - Deepti Goyal
- Department of Chemistry, Faculty of Basic and Applied Sciences Sri Guru Granth Sahib World University Fatehgarh Sahib India
| | - Bhupesh Goyal
- School of Chemistry & Biochemistry Thapar Institute of Engineering & Technology Patiala India
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8
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Dalal A, Khanna R, Kamboj RC. Photochemical Transformation of some 3-benzyloxy-2-(benzo[ b]thiophen-2-yl)-4 Hchromen-4-ones: A Remote Substituent Effect. OPEN CHEM 2018. [DOI: 10.1515/chem-2018-0009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
The effect on photochemical transformations of the substituents present remotely from the reaction site in 3-benzyloxy-2-(benzo[b]thiophen-2-yl)-4H-chromen-4-ones has been determined. The structure(s) of the substrates and photoproducts were established by spectroscopic techniques (UV, IR, and NMR). The substituents had profound effects on product yield and distribution. Electron withdrawing groups (EWGs) on the benzenoid moiety of the chromenone nucleus increased the yield of the photoproducts whereas electron donating groups (EDGs) decreased the yield. These results may be attributed to “state switching” of the substituents during excitation.
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Affiliation(s)
- Aarti Dalal
- Department of Chemistry , Kurukshetra University , Kurukshetra-136119 , Haryana , India
| | - Radhika Khanna
- Department of Chemistry , Kurukshetra University , Kurukshetra-136119 , Haryana , India
| | - Ramesh C. Kamboj
- Department of Chemistry , Kurukshetra University , Kurukshetra-136119 , Haryana , India
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9
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Cornilescu G, Ramos Alvarenga RF, Wyche TP, Bugni TS, Gil RR, Cornilescu CC, Westler WM, Markley JL, Schwieters CD. Progressive Stereo Locking (PSL): A Residual Dipolar Coupling Based Force Field Method for Determining the Relative Configuration of Natural Products and Other Small Molecules. ACS Chem Biol 2017; 12:2157-2163. [PMID: 28617580 DOI: 10.1021/acschembio.7b00281] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Establishing the relative configuration of a bioactive natural product represents the most challenging part in determining its structure. Residual dipolar couplings (RDCs) are sensitive probes of the relative spatial orientation of internuclear vectors. We adapted a force field structure calculation methodology to allow free sampling of both R and S configurations of the stereocenters of interest. The algorithm uses a floating alignment tensor in a simulated annealing protocol to identify the conformations and configurations that best fit experimental RDC and distance restraints (from NOE and J-coupling data). A unique configuration (for rigid molecules) or a very small number of configurations (for less rigid molecules) of the structural models having the lowest chiral angle energies and reasonable magnitudes of the alignment tensor are provided as the best predictions of the unknown configuration. For highly flexible molecules, the progressive locking of their stereocenters into their statistically dominant R or S state dramatically reduces the number of possible relative configurations. The result is verified by checking that the same configuration is obtained by initiating the locking from different regions of the molecule. For all molecules tested having known configurations (with conformations ranging from mostly rigid to highly flexible), the method accurately determined the correct configuration.
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Affiliation(s)
| | - René F. Ramos Alvarenga
- Pharmaceutical
Sciences Division, School of Pharmacy, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Thomas P. Wyche
- Pharmaceutical
Sciences Division, School of Pharmacy, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
- Biological
Chemistry and Molecular Pharmacology Department, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Tim S. Bugni
- Pharmaceutical
Sciences Division, School of Pharmacy, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Roberto R. Gil
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | | | | | | | - Charles D. Schwieters
- Center for
Information Technology, National Institutes of Health, Bethesda, Maryland 20892-5624, United States
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10
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Nagae H, Kundu A, Tsurugi H, Mashima K. Propargylic C(sp3)–H Bond Activation for Preparing η3-Propargyl/Allenyl Complexes of Yttrium. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00395] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Haruki Nagae
- Department of Chemistry,
Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Abhinanda Kundu
- Department of Chemistry,
Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hayato Tsurugi
- Department of Chemistry,
Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Kazushi Mashima
- Department of Chemistry,
Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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11
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Evich M, Spring-Connell AM, Germann MW. Impact of modified ribose sugars on nucleic acid conformation and function. HETEROCYCL COMMUN 2017. [DOI: 10.1515/hc-2017-0056] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
AbstractThe modification of the ribofuranose in nucleic acids is a widespread method of manipulating the activity of nucleic acids. These alterations, however, impact the local conformation and chemical reactivity of the sugar. Changes in the conformation and dynamics of the sugar moiety alter the local and potentially global structure and plasticity of nucleic acids, which in turn contributes to recognition, binding of ligands and enzymatic activity of proteins. This review article introduces the conformational properties of the (deoxy)ribofuranose ring and then explores sugar modifications and how they impact local and global structure and dynamics in nucleic acids.
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Affiliation(s)
- Marina Evich
- Georgia State University, Department of Chemistry, 50 Decatur St. SE, Atlanta, GA 30303, USA
| | | | - Markus W. Germann
- Georgia State University, Department of Chemistry, 50 Decatur St. SE, Atlanta, GA 30303, USA
- Georgia State University, Department of Biology, P.O. 4010, Atlanta, GA 30303, USA
- Georgia State University, Neuroscience Institute, P.O. 5030, Atlanta, GA 30303, USA
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12
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Yamamoto K, Higashida K, Nagae H, Tsurugi H, Mashima K. Synthesis and Characterization of Heterobimetallic Tantalum-Rhodium and Tantalum-Iridium Complexes Connected by a Tantalacyclopentadiene Fragment. Helv Chim Acta 2016. [DOI: 10.1002/hlca.201600180] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Keishi Yamamoto
- Department of Chemistry; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
| | - Kosuke Higashida
- Department of Chemistry; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
| | - Haruki Nagae
- Department of Chemistry; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
| | - Hayato Tsurugi
- Department of Chemistry; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
| | - Kazushi Mashima
- Department of Chemistry; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
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13
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Bhowmick A, Brookes DH, Yost SR, Dyson HJ, Forman-Kay JD, Gunter D, Head-Gordon M, Hura GL, Pande VS, Wemmer DE, Wright PE, Head-Gordon T. Finding Our Way in the Dark Proteome. J Am Chem Soc 2016; 138:9730-42. [PMID: 27387657 PMCID: PMC5051545 DOI: 10.1021/jacs.6b06543] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The traditional structure-function paradigm has provided significant insights for well-folded proteins in which structures can be easily and rapidly revealed by X-ray crystallography beamlines. However, approximately one-third of the human proteome is comprised of intrinsically disordered proteins and regions (IDPs/IDRs) that do not adopt a dominant well-folded structure, and therefore remain "unseen" by traditional structural biology methods. This Perspective considers the challenges raised by the "Dark Proteome", in which determining the diverse conformational substates of IDPs in their free states, in encounter complexes of bound states, and in complexes retaining significant disorder requires an unprecedented level of integration of multiple and complementary solution-based experiments that are analyzed with state-of-the art molecular simulation, Bayesian probabilistic models, and high-throughput computation. We envision how these diverse experimental and computational tools can work together through formation of a "computational beamline" that will allow key functional features to be identified in IDP structural ensembles.
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Affiliation(s)
- Asmit Bhowmick
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720
| | - David H. Brookes
- Department of Chemistry, University of California, Berkeley, CA 94720
| | - Shane R. Yost
- Department of Chemistry, University of California, Berkeley, CA 94720
| | - H. Jane Dyson
- Department of Integrative Structural and Computational Biology, Scripps Research Institute, La Jolla, California 92037
| | - Julie D. Forman-Kay
- Molecular Structure and Function Program, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Daniel Gunter
- Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley CA, 94720
| | | | - Gregory L. Hura
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA, 94720
| | - Vijay S. Pande
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - David E. Wemmer
- Department of Chemistry, University of California, Berkeley, CA 94720
| | - Peter E. Wright
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Teresa Head-Gordon
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720
- Department of Chemistry, University of California, Berkeley, CA 94720
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA, 94720
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14
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Ahalawat N, Arora S, Murarka RK. Structural Ensemble of CD4 Cytoplasmic Tail (402–419) Reveals a Nearly Flat Free-Energy Landscape with Local α-Helical Order in Aqueous Solution. J Phys Chem B 2015; 119:11229-42. [DOI: 10.1021/acs.jpcb.5b03092] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Navjeet Ahalawat
- Department
of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
| | - Simran Arora
- Department
of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
| | - Rajesh K. Murarka
- Department
of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal By-pass Road, Bhauri, Bhopal 462066, Madhya Pradesh, India
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15
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Xu L, Chen Y, Wang X. Dual effects of familial Alzheimer's disease mutations (D7H, D7N, and H6R) on amyloid β peptide: Correlation dynamics and zinc binding. Proteins 2014; 82:3286-97. [DOI: 10.1002/prot.24669] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 07/17/2014] [Accepted: 08/11/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Liang Xu
- School of Chemistry; Dalian University of Technology; Dalian China
| | - Yonggang Chen
- Network and Information Center, Dalian University of Technology; Dalian China
| | - Xiaojuan Wang
- School of Chemical Machinery, Dalian University of Technology; Dalian China
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16
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Ball KA, Wemmer DE, Head-Gordon T. Comparison of structure determination methods for intrinsically disordered amyloid-β peptides. J Phys Chem B 2014; 118:6405-16. [PMID: 24410358 PMCID: PMC4066902 DOI: 10.1021/jp410275y] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Intrinsically disordered proteins (IDPs) represent a new frontier in structural biology since the primary characteristic of IDPs is that structures need to be characterized as diverse ensembles of conformational substates. We compare two general but very different ways of combining NMR spectroscopy with theoretical methods to derive structural ensembles for the disease IDPs amyloid-β 1-40 and amyloid-β 1-42, which are associated with Alzheimer's Disease. We analyze the performance of de novo molecular dynamics and knowledge-based approaches for generating structural ensembles by assessing their ability to reproduce a range of NMR experimental observables. In addition to the comparison of computational methods, we also evaluate the relative value of different types of NMR data for refining or validating the IDP structural ensembles for these important disease peptides.
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Affiliation(s)
- K Aurelia Ball
- Graduate Group in Biophysics , Berkeley, California 94720, United States
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17
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Rawat A, Kumar D. NMR investigations of structural and dynamics features of natively unstructured drug peptide - salmon calcitonin: implication to rational design of potent sCT analogs. J Pept Sci 2012. [DOI: 10.1002/psc.2471] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Atul Rawat
- Centre of Biomedical Magnetic Resonance; Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raibareli Road; Lucknow-; 226014; India
| | - Dinesh Kumar
- Centre of Biomedical Magnetic Resonance; Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raibareli Road; Lucknow-; 226014; India
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18
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Abstract
Protein aggregation is believed to be responsible for a number of human diseases and limits the yields of pharmaceutical proteins during production. Computer simulations can be used to develop novel experimentally testable hypotheses pertaining to aggregation. While all-atom simulations with explicit solvent are too computationally intensive to address the multitude of relevant time scales, coarse-grained models make it possible to observe the transition of monomers to an equilibrium containing aggregates. Here, we provide the reader with background information and a list of steps for setting up, performing, and analyzing computer simulations of aggregating coarse-grained (CG) proteins.
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Affiliation(s)
- Troy Cellmer
- Laboratory of Chemical Physics, National Institute of Digestive and Diabetes and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA.
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Ball KA, Phillips AH, Nerenberg PS, Fawzi NL, Wemmer DE, Head-Gordon T. Homogeneous and heterogeneous tertiary structure ensembles of amyloid-β peptides. Biochemistry 2011; 50:7612-28. [PMID: 21797254 DOI: 10.1021/bi200732x] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The interplay of modern molecular simulation and high-quality nuclear magnetic resonance (NMR) experiments has reached a fruitful stage for quantitative characterization of structural ensembles of disordered peptides. Amyloid-β 1-42 (Aβ42), the primary peptide associated with Alzheimer's disease, and fragments such as Aβ21-30 are both classified as intrinsically disordered peptides (IDPs). We use a variety of NMR observables to validate de novo molecular dynamics simulations in explicit water to characterize the tertiary structure ensemble of Aβ42 and Aβ21-30 from the perspective of their classification as IDPs. Unlike the Aβ21-30 fragment that conforms to expectations of an IDP that is primarily extended, we find that Aβ42 samples conformations reflecting all possible secondary structure categories and spans the range of IDP classifications from collapsed structured states to highly extended conformations, making it an IDP with a far more heterogeneous tertiary ensemble.
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Affiliation(s)
- K Aurelia Ball
- Graduate Group in Biophysics, University of California, Berkeley, California 94720, United States
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Kamboj RC, Arora R, Kumar D, Sharma G. Photo-reorganization of 3-alkoxy-6-chloro-2-(thiophen-3-yl)-4H-chromen-4-ones: Regioselective cyclization via γ-hydrogen abstraction. J Photochem Photobiol A Chem 2011. [DOI: 10.1016/j.jphotochem.2011.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kamboj RC, Kumar D, Sharma G, Arora R. Photochemical Transformations of Some 2-(5-Methylthiophen-2-yl)-3-[(naphthalen-2-yl)methoxy]-4H-chromen-4-ones Involving Type-II Process. CHINESE J CHEM 2011. [DOI: 10.1002/cjoc.201190151] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Freyer W. 15N-markierte Verbindungen in der organischen ChemieBeziehungen zwischen Struktur und 15N-Kopplungskonstanten. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/zfch.19810210203] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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23
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Dreeskamp H, Sackmann E, Stegmeier G. Die Vorzeichen der C13-H Kernspinkopplungskonstanten in Propin. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19630670904] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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24
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Kumar D, Chugh J, Sharma S, Hosur RV. Conserved structural and dynamics features in the denatured states of drosophila SUMO, human SUMO and ubiquitin proteins: Implications to sequence-folding paradigm. Proteins 2008; 76:387-402. [DOI: 10.1002/prot.22354] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Fawzi NL, Phillips AH, Ruscio JZ, Doucleff M, Wemmer DE, Head-Gordon T. Structure and dynamics of the Abeta(21-30) peptide from the interplay of NMR experiments and molecular simulations. J Am Chem Soc 2008; 130:6145-58. [PMID: 18412346 PMCID: PMC3474854 DOI: 10.1021/ja710366c] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We combine molecular dynamics simulations and new high-field NMR experiments to describe the solution structure of the Abeta(21-30) peptide fragment that may be relevant for understanding structural mechanisms related to Alzheimer's disease. By using two different empirical force-field combinations, we provide predictions of the three-bond scalar coupling constants ((3)J(H(N)H(alpha))), chemical-shift values, (13)C relaxation parameters, and rotating-frame nuclear Overhauser effect spectroscopy (ROESY) crosspeaks that can then be compared directly to the same observables measured in the corresponding NMR experiment of Abeta(21-30). We find robust prediction of the (13)C relaxation parameters and medium-range ROESY crosspeaks by using new generation TIP4P-Ew water and Amber ff99SB protein force fields, in which the NMR validates that the simulation yields both a structurally and dynamically correct ensemble over the entire Abeta(21-30) peptide. Analysis of the simulated ensemble shows that all medium-range ROE restraints are not satisfied simultaneously and demonstrates the structural diversity of the Abeta(21-30) conformations more completely than when determined from the experimental medium-range ROE restraints alone. We find that the structural ensemble of the Abeta(21-30) peptide involves a majority population (approximately 60%) of unstructured conformers, lacking any secondary structure or persistent hydrogen-bonding networks. However, the remaining minority population contains a substantial percentage of conformers with a beta-turn centered at Val24 and Gly25, as well as evidence of the Asp23 to Lys28 salt bridge important to the fibril structure. This study sets the stage for robust theoretical work on Abeta(1-40) and Abeta(1-42), for which collection of detailed NMR data on the monomer will be more challenging because of aggregation and fibril formation on experimental timescales at physiological conditions. In addition, we believe that the interplay of modern molecular simulation and high-quality NMR experiments has reached a fruitful stage for characterizing structural ensembles of disordered peptides and proteins in general.
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Affiliation(s)
- Nicolas L. Fawzi
- UCSF/UC Berkeley Joint Graduate Group in Bioengineering, Berkeley, California 94720
| | - Aaron H. Phillips
- Department of Chemistry, University of California, Berkeley, California 94720
| | - Jory Z. Ruscio
- Department of Bioengineering, University of California, Berkeley, California 94720
| | - Michaeleen Doucleff
- Department of Chemistry, University of California, Berkeley, California 94720
| | - David E. Wemmer
- Department of Chemistry, University of California, Berkeley, California 94720
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Teresa Head-Gordon
- UCSF/UC Berkeley Joint Graduate Group in Bioengineering, Berkeley, California 94720
- Department of Bioengineering, University of California, Berkeley, California 94720
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
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Hupbach U, Frischleder H, Helbig H. Berechnung der13C-H- und der13C-13C-Kopplung mit der Methode der Separierten Elektronenpaare. Mol Phys 2006. [DOI: 10.1080/00268976900100661] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Yokozeki A, Bauer SH. The geometric and dynamic structures of fluorocarbons and related compounds. Top Curr Chem (Cham) 2006:71-119. [PMID: 1094588 DOI: 10.1007/bfb0045411] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Fraenkel G, Chow A, Fleischer R, Liu H. Perturbation of Conjugation in Allylic Lithium Compounds Due to Stereochemical Control of Internal Lithium Coordination: Crystallography, NMR, and Calculational Studies. J Am Chem Soc 2004; 126:3983-95. [PMID: 15038753 DOI: 10.1021/ja030370y] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Several allylic lithium compounds have been prepared with ligands tethered at C(2). These are with (CH(3)OCH(2)CH(2))(2)NCH(2)-, 6, 1-TMS 5, 1,3-bis(TMS) 8, and 1,1,3-tris(TMS) 9. Allylic lithiums with (CH(3)OCH(2)CH(2))(2)NCH(2)C(CH(3))(2)-, are 10, 1-TMS 11, and 1,3-bis(TMS), 12 compounds with -C(CH(3))(2)CH(2)N-((S)-(2-methoxymethyl)-pyrrolidino) at C(2) 13, 1-TMS 14, and 1,3-bis(TMS) 15. In the solid state, 8-10 and 12 are monomers, 6 and 13 are Li-bridged dimers, and 5 and 7 are polymers. In solution (NMR data), 5, 7-12, 14, and 15 are monmeric, and 6 is a dimer. All samples show lithium to be closest to one of the terminal allyl carbons in the crystal structures and to exhibit one-bond (13)C-(7)Li or (13)C(1)-(7)Li spin coupling, for the former typically ca. 3 Hz and for the latter 6-8 Hz. In every structure, the C(1)-C(2) allyl bond is longer than the C(2)-C(3) bond, and both lie between those for solvated delocalized and unsolvated localized allylic lithium compounds, respectively, as is also the case for the terminal allyl (13)C NMR shifts. Lithium lies 40-70 degrees off the axis perpendicular to the allyl plane at C(1). These effects are variable, so the trend is that the differences between the C(1)-C(2) and C(2)-C(3) bond lengths, (13)delta(3)-(13)delta(1) values, and the (13)C(1)-(7)Li or (13)C-(6)Li coupling constants all increase with decreasing values of the torsional angle that C(1)-Li makes with respect to the allyl plane.
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Affiliation(s)
- Gideon Fraenkel
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210-1185, USA.
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Fraenkel G, Duncan JH, Martin K, Wang J. Stereochemistry of Solvation of Benzylic Lithium Compounds: Structure and Dynamic Behavior. J Am Chem Soc 1999. [DOI: 10.1021/ja990485v] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gideon Fraenkel
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Joseph H. Duncan
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Kevin Martin
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Jinhai Wang
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
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Fraenkel G, Duncan JH, Wang J. Restricted Stereochemistry of Solvation of Allylic Lithium Compounds: Structural and Dynamic Consequences. J Am Chem Soc 1998. [DOI: 10.1021/ja983047h] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gideon Fraenkel
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Joseph H. Duncan
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Jinhai Wang
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
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Faibish NC, Park YS, Lee S, Beak P. A Mechanistic and Structural Investigation of the (−)-Sparteine Mediated Asymmetric Benzylic Lithiation Substitution Reactions of N-Boc-N-(p-methoxyphenyl)benzylamine. J Am Chem Soc 1997. [DOI: 10.1021/ja972225o] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Neil C. Faibish
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Yong Sun Park
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Steven Lee
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Peter Beak
- Contribution from the Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
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Fraenkel G, Qiu F. Partially Delocalized Allylic Lithium Compounds: Dynamics of Inversion, 1,3 Li Shift, and C−Li Bond, Exchange Influence of the Stereochemistry of Solvation. J Am Chem Soc 1997. [DOI: 10.1021/ja963083l] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gideon Fraenkel
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
| | - Fayang Qiu
- Contribution from the Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
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Surján PR. The role of hybridization in perturbative bond theories: The existence of exact strictly localized orbitals in small molecules. ACTA ACUST UNITED AC 1988. [DOI: 10.1016/0166-1280(88)80252-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lazzeretti P, Rossi E, Taddei F, Zanasi R. Theoretical determination of the nuclear spin–spin coupling tensors in NH−2, NH+4, BH−4molecular ions. J Chem Phys 1982. [DOI: 10.1063/1.444056] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Laussac JP. Comportement de Ligands Phosphorés Potentiellement Bidentates vis-à-vis de AlCl3 et de Al[OCH(CF3)2]3. Etude RMN (1H,13C,27Al,31P). ACTA ACUST UNITED AC 1979. [DOI: 10.1002/mrc.1270120414] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Günther H, Seel H, Günther ME. Carbon-13,1H coupling constants for benzene and the tropylium ion. ACTA ACUST UNITED AC 1978. [DOI: 10.1002/mrc.1270110208] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Joela H. Theoretical nuclear spin-spin coupling constants using atom-atom polarizabilities.13CH and HH′ coupling constants of some [2.2.1] bicyclic compounds using the INDO approximation. ACTA ACUST UNITED AC 1977. [DOI: 10.1002/mrc.1270090611] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Vogeli U, von Philipsborn W. Vicinal C,H spin coupling in substituted alkenes. Stereochemical significance and structural effects. ACTA ACUST UNITED AC 1975. [DOI: 10.1002/mrc.1270071213] [Citation(s) in RCA: 222] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Miertuś S, Boča R, Pelikán P, Valko L. Maximum overlap approximation calculations on polyatomic molecules. Chem Phys 1975. [DOI: 10.1016/0301-0104(75)80003-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Dreeskamp H, Hildenbrand K. Kernspinkopplungskonstanten und Elektronenstrukturen siliciumorganischer Verbindungen. European J Org Chem 1975. [DOI: 10.1002/jlac.197519750413] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Schaeffer C, Zuckerman J. Pulsed fourier transform NMR of substituted aryltrimethyltin derivatives. J Organomet Chem 1974. [DOI: 10.1016/s0022-328x(00)80486-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Ando I, Nishioka A, Kambe M. Directly Bonded Carbon-Hydrogen Coupling Constants of n-Pentane. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1972. [DOI: 10.1246/bcsj.45.3306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Summerhays KD, Maciel GE. A pseudo-atom molecular orbital approach to substituent effects in organic compounds. Mol Phys 1972. [DOI: 10.1080/00268977200102051] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Signs of spin-spin interaction constants in trans-acetylformamide-15N. Russ Chem Bull 1969. [DOI: 10.1007/bf00906550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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