1
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Sun Z, He Q, Gong Z, Kalhor P, Huai Z, Liu Z. A General Picture of Cucurbit[8]uril Host–Guest Binding: Recalibrating Bonded Interactions. Molecules 2023; 28:molecules28073124. [PMID: 37049887 PMCID: PMC10095826 DOI: 10.3390/molecules28073124] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/15/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023] Open
Abstract
Atomic-level understanding of the dynamic feature of host–guest interactions remains a central challenge in supramolecular chemistry. The remarkable guest binding behavior of the Cucurbiturils family of supramolecular containers makes them promising drug carriers. Among Cucurbit[n]urils, Cucurbit[8]uril (CB8) has an intermediate portal size and cavity volume. It can exploit almost all host–guest recognition motifs formed by this host family. In our previous work, an extensive computational investigation of the binding of seven commonly abused and structurally diverse drugs to the CB8 host was performed, and a general dynamic binding picture of CB8-guest interactions was obtained. Further, two widely used fixed-charge models for drug-like molecules were investigated and compared in great detail, aiming at providing guidelines in choosing an appropriate charge scheme in host-guest modelling. Iterative refitting of atomic charges leads to improved binding thermodynamics and the best root-mean-squared deviation from the experimental reference is 2.6 kcal/mol. In this work, we focus on a thorough evaluation of the remaining parts of classical force fields, i.e., the bonded interactions. The widely used general Amber force fields are assessed and refitted with generalized force-matching to improve the intra-molecular conformational preference, and thus the description of inter-molecular host–guest interactions. The interaction pattern and binding thermodynamics show a significant dependence on the modelling parameters. The refitted system-specific parameter set improves the consistency of the modelling results and the experimental reference significantly. Finally, combining the previous charge-scheme comparison and the current force-field refitting, we provide general guidelines for the theoretical modelling of host–guest binding.
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2
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Castelli M, Doria F, Freccero M, Colombo G, Moroni E. Studying the Dynamics of a Complex G-Quadruplex System: Insights into the Comparison of MD and NMR Data. J Chem Theory Comput 2022; 18:4515-4528. [PMID: 35666124 PMCID: PMC9281369 DOI: 10.1021/acs.jctc.2c00291] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
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Molecular dynamics
(MD) simulations are coming of age in the study
of nucleic acids, including specific tertiary structures such as G-quadruplexes.
While being precious for providing structural and dynamic information
inaccessible to experiments at the atomistic level of resolution,
MD simulations in this field may still be limited by several factors.
These include the force fields used, different models for ion parameters,
ionic strengths, and water models. We address various aspects of this
problem by analyzing and comparing microsecond-long atomistic simulations
of the G-quadruplex structure formed by the human immunodeficiency
virus long terminal repeat (HIV LTR)-III sequence for which nuclear
magnetic resonance (NMR) structures are available. The system is studied
in different conditions, systematically varying the ionic strengths,
ion numbers, and water models. We comparatively analyze the dynamic
behavior of the G-quadruplex motif in various conditions and assess
the ability of each simulation to satisfy the nuclear magnetic resonance
(NMR)-derived experimental constraints and structural parameters.
The conditions taking into account K+-ions to neutralize
the system charge, mimicking the intracellular ionic strength, and
using the four-atom water model are found to be the best in reproducing
the experimental NMR constraints and data. Our analysis also reveals
that in all of the simulated environments residues belonging to the
duplex moiety of HIV LTR-III exhibit the highest flexibility.
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Affiliation(s)
- Matteo Castelli
- Department of Chemistry, University of Pavia, V.le Taramelli 12, 27100 Pavia, Italy
| | - Filippo Doria
- Department of Chemistry, University of Pavia, V.le Taramelli 12, 27100 Pavia, Italy
| | - Mauro Freccero
- Department of Chemistry, University of Pavia, V.le Taramelli 12, 27100 Pavia, Italy
| | - Giorgio Colombo
- Department of Chemistry, University of Pavia, V.le Taramelli 12, 27100 Pavia, Italy.,Institute of Chemical Sciences and Technologies SCITEC-CNR, Via Mario Bianco, 9, 20131 Milano, Italy
| | - Elisabetta Moroni
- Institute of Chemical Sciences and Technologies SCITEC-CNR, Via Mario Bianco, 9, 20131 Milano, Italy
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3
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Green AT, Pickard AJ, Li R, MacKerell AD, Bierbach U, Cho SS. Computational and Experimental Characterization of rDNA and rRNA G-Quadruplexes. J Phys Chem B 2022; 126:609-619. [PMID: 35026949 DOI: 10.1021/acs.jpcb.1c08340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
DNA G-quadruplexes in human telomeres and gene promoters are being extensively studied for their role in controlling the growth of cancer cells. G-quadruplexes have been unambiguously shown to exist both in vitro and in vivo, including in the guanine (G)-rich DNA genes encoding pre-ribosomal RNA (pre-rRNA), which is transcribed in the cell's nucleolus. Recent studies strongly suggest that these DNA sequences ("rDNA"), and the transcribed rRNA, are a potential anticancer target through the inhibition of RNA polymerase I (Pol I) in ribosome biogenesis, but the structures of ribosomal G-quadruplexes at atomic resolution are unknown and very little biophysical characterization has been performed on them to date. In the present study, circular dichroism (CD) spectroscopy is used to show that two putative rDNA G-quadruplex sequences, NUC 19P and NUC 23P and their counterpart rRNAs, predominantly adopt parallel topologies, reminiscent of the analogous telomeric quadruplex structures. Based on this information, we modeled parallel topology atomistic structures of the putative ribosomal G-quadruplexes. We then validated and refined the modeled ribosomal G-quadruplex structures using all-atom molecular dynamics (MD) simulations with the CHARMM36 force field in the presence and absence of stabilizing K+. Motivated by preliminary MD simulations of the telomeric parallel G-quadruplex (TEL 24P) in which the K+ ion is expelled, we used updated CHARMM36 force field K+ parameters that were optimized, targeting the data from quantum mechanical calculations and the polarizable Drude model force field. In subsequent MD simulations with optimized CHARMM36 parameters, the K+ ions are predominantly in the G-quadruplex channel and the rDNA G-quadruplexes have more well-defined, predominantly parallel-topology structures as compared to rRNA. In addition, NUC 19P is more structured than NUC 23P, which contains extended loops. Results from this study set the structural foundation for understanding G-quadruplex functions and the design of novel chemotherapeutics against these nucleolar targets and can be readily extended to other DNA and RNA G-quadruplexes.
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Affiliation(s)
- Adam T Green
- Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27109, United States
| | - Amanda J Pickard
- Department of Chemistry, Wake Forest University, Wake Downtown Campus, Winston-Salem, North Carolina 27101, United States
| | - Rongzhong Li
- Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27109, United States.,Department of Computer Science, Wake Forest University, Winston-Salem, North Carolina 27109, United States
| | - Alexander D MacKerell
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201, United States
| | - Ulrich Bierbach
- Department of Chemistry, Wake Forest University, Wake Downtown Campus, Winston-Salem, North Carolina 27101, United States
| | - Samuel S Cho
- Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27109, United States.,Department of Computer Science, Wake Forest University, Winston-Salem, North Carolina 27109, United States
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4
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Sun Z, Huai Z, He Q, Liu Z. A General Picture of Cucurbit[8]uril Host-Guest Binding. J Chem Inf Model 2021; 61:6107-6134. [PMID: 34818004 DOI: 10.1021/acs.jcim.1c01208] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Describing, understanding, and designing complex interaction networks within macromolecular systems remain challenging in modern chemical research. Host-guest systems, despite their relative simplicity in both the structural feature and interaction patterns, still pose problems in theoretical modeling. The barrel-shaped supramolecular container cucurbit[8]uril (CB8) shows promising functionalities in various areas, e.g., catalysis and molecular recognition. It can stably coordinate a series of structurally diverse guests with high affinities. In this work, we examine the binding of seven commonly abused drugs to the CB8 host, aiming at providing a general picture of CB8-guest binding. Extensive sampling of the configurational space of these host-guest systems is performed, and the binding pathway and interaction patterns of CB8-guest complexes are investigated. A thorough comparison of widely used fixed-charge models for drug-like molecules is presented. Iterative refitting of the atomic charges suggests significant conformation dependence of charge generation. The initial model generated at the original conformation could be inaccurate for new conformations explored during conformational search, and the newly fitted charge set improves the prediction-experiment correlation significantly. Our investigations of the configurational space of CB8-drug complexes suggest that the host-guest interactions are more complex than expected. Despite the structural simplicities of these molecules, the conformational fluctuations of the host and the guest molecules and orientations of functional groups lead to the existence of an ensemble of binding modes. The insights of the binding thermodynamics, performance of fixed-charge models, and binding patterns of the CB8-guest systems are useful for studying and elucidating the binding mechanism of other host-guest complexes.
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Affiliation(s)
- Zhaoxi Sun
- Beijing National Laboratory for Molecular Sciences, Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Zhe Huai
- XtalPi-AI Research Center (XARC), 9F, Tower A, Dongsheng Building, No. 8, Zhongguancun East Road, Haidian District, Beijing 100083, P.R. China
| | - Qiaole He
- AI Department of Enzymaster (Ningbo) Bio-Engineering Co., Ltd., North Century Avenue 333, Ningbo 315100, China
| | - Zhirong Liu
- Beijing National Laboratory for Molecular Sciences, Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
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5
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Li N, Gao Y, Qiu F, Zhu T. Benchmark Force Fields for the Molecular Dynamic Simulation of G-Quadruplexes. Molecules 2021; 26:5379. [PMID: 34500812 PMCID: PMC8434458 DOI: 10.3390/molecules26175379] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 11/29/2022] Open
Abstract
G-quadruplexes have drawn widespread attention for serving as a potential anti-cancer target and their application in material science. Molecular dynamics (MD) simulation is the key theoretical tool in the study of GQ's structure-function relationship. In this article, we systematically benchmarked the five force fields of parmbsc0, parmbsc1, OL15, AMOEBA, and Drude2017 on the MD simulation of G-quadruplex from four aspects: structural stability, central ion channel stability, description of Hoogsteen hydrogen bond network, and description of the main chain dihedral angle. The results show that the overall performance of the Drude force field is the best. Although there may be a certain over-polarization effect, it is still the best choice for the MD simulation of G-quadruplexes.
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Affiliation(s)
- Na Li
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China;
| | - Ya Gao
- School of Mathematics, Physics and Statistics, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Feng Qiu
- Institute of Artificial Intelligence on Education, Shanghai Normal University, Shanghai 200234, China
| | - Tong Zhu
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China;
- NYU-ECNU Center for Computational Chemistry, New York University Shanghai, Shanghai 200062, China
- Shandong Key Laboratory of Biophysics, Institute of Biophysics, Dezhou University, Dezhou 253023, China
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6
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Ratnasinghe BD, Salsbury AM, Lemkul JA. Ion Binding Properties and Dynamics of the bcl-2 G-Quadruplex Using a Polarizable Force Field. J Chem Inf Model 2020; 60:6476-6488. [PMID: 33264004 DOI: 10.1021/acs.jcim.0c01064] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
G-quadruplexes (GQs) are topologically diverse, highly thermostable noncanonical nucleic acid structures that form in guanine-rich sequences in DNA and RNA. GQs are implicated in transcriptional and translational regulation and genome maintenance, and deleterious alterations to their structures contribute to diseases such as cancer. The expression of the B-cell lymphoma 2 (Bcl-2) antiapoptotic protein, for example, is under transcriptional control of a GQ in the promoter of the bcl-2 gene. Modulation of the bcl-2 GQ by small molecules is of interest for chemotherapeutic development but doing so requires knowledge of the factors driving GQ folding and stabilization. To develop a greater understanding of the electrostatic properties of the bcl-2 promoter GQ, we performed molecular dynamics simulations using the Drude-2017 polarizable force field and compared relevant outcomes to the nonpolarizable CHARMM36 force field. Our simulation outcomes highlight the importance of dipole-dipole interactions in the bcl-2 GQ, particularly during the recruitment of a bulk K+ ion to the solvent-exposed face of the tetrad stem. We also predict and characterize an "electronegative pocket" at the tetrad-long loop junction that induces local backbone conformational change and may induce local conformational changes at cellular concentrations of K+. These outcomes suggest that moieties within the bcl-2 GQ can be targeted by small molecules to modulate bcl-2 GQ stability.
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Affiliation(s)
- Brian D Ratnasinghe
- Department of Biochemistry, Virginia Tech, 303 Engel Hall, 340 West Campus Dr., Blacksburg, Virginia 24061, United States
| | - Alexa M Salsbury
- Department of Biochemistry, Virginia Tech, 303 Engel Hall, 340 West Campus Dr., Blacksburg, Virginia 24061, United States
| | - Justin A Lemkul
- Department of Biochemistry and Center for Drug Discovery, Virginia Tech, 303 Engel Hall, 340 West Campus Dr., Blacksburg, Virginia 24061, United States
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7
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Balasubramanian S, Senapati S. Dynamics and Barrier of Movements of Sodium and Potassium Ions Across the Oxytricha nova G-Quadruplex Core. J Phys Chem B 2020; 124:11055-11066. [PMID: 33238706 DOI: 10.1021/acs.jpcb.0c04826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
G-quadruplexes (GQs) are highly stable noncanonical forms of nucleic acids that are present in important genomic regions. The central core of the GQ is lined up by four closely spaced carbonyl groups from the G-quartets, and the resulting electrostatic repulsion is neutralized by the coordinating cations. In spite of several reports on GQ structure and cation-GQ interactions, the atomic- to molecular-level understanding of the ion dynamics and ion exchange in the GQ core is quite poor. Here, we attempt to elucidate the mechanism of Na+ and K+ binding to the GQ core and trace the exchange of these ions with the ions in bulk by means of all-atomic molecular dynamics (MD) simulations. One of the most studied GQs, Oxytricha nova telomeric G-quadruplex (OxyGQ), is taken as the representative GQ. Subsequently, umbrella sampling MD simulations were performed to elucidate the energetics of ion translocation from one end to the other end of the GQ central core. Our study highlights the importance of ion hydration for the uptake and correct positioning of the cations in the core. The free-energy landscape of ion transport has shown favorable in-plane binding of Na+ ions with GQ quartets, which matches very well with the crystal structure. The binding of K+ ions, on the other hand, was out-of-plane and its translocation required a larger barrier to cross.
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Affiliation(s)
- Sangeetha Balasubramanian
- Department of Biotechnology, BJM School of Biosciences, Indian Institute of Technology Madras, Chennai 600 036, India
| | - Sanjib Senapati
- Department of Biotechnology, BJM School of Biosciences, Indian Institute of Technology Madras, Chennai 600 036, India
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8
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Salsbury AM, Dean TJ, Lemkul JA. Polarizable Molecular Dynamics Simulations of Two c-kit Oncogene Promoter G-Quadruplexes: Effect of Primary and Secondary Structure on Loop and Ion Sampling. J Chem Theory Comput 2020; 16:3430-3444. [PMID: 32307997 DOI: 10.1021/acs.jctc.0c00191] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
G-quadruplexes (GQs) are highly ordered nucleic acid structures that play fundamental roles in regulating gene expression and maintaining genomic stability. GQs are topologically diverse and enriched in promoter sequences of growth regulatory genes and proto-oncogenes, suggesting that they may serve as attractive targets for drug design at the level of transcription rather than inhibiting the activity of the protein products of these genes. The c-kit promoter contains three adjacent GQ-forming sequences that have proposed antagonistic effects on gene expression and thus are promising drug targets for diseases such as gastrointestinal stromal tumors, mast cell disease, and leukemia. Because GQ stability is influenced by primary structure, secondary structure, and ion interactions, a greater understanding of GQ structure, dynamics, and ion binding properties is needed to develop novel, GQ-targeting therapeutics. Here, we performed molecular dynamics simulations to systematically study the c-kit2 and c-kit* GQs, evaluating nonpolarizable and polarizable force fields (FFs) and examining the effects of base substitutions and cation type (K+, Na+, and Li+) on the dynamics of their isolated and linked structures. We found that the Drude polarizable FF outperformed the additive CHARMM36 FF in two- and three-tetrad GQs and solutions of KCl, NaCl, and LiCl. Drude simulations with different cations agreed with the known GQ stabilization preference (K+ > Na+ > Li+) and illustrated that tetrad core-ion coordination differs as a function of cation type. Finally, we showed that differences in primary and secondary structure influence loop sampling, ion binding, and core-ion energetics of GQs.
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Affiliation(s)
- Alexa M Salsbury
- Department of Biochemistry and Center for Drug Discovery, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Tanner J Dean
- Department of Biochemistry and Center for Drug Discovery, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Justin A Lemkul
- Department of Biochemistry and Center for Drug Discovery, Virginia Tech, Blacksburg, Virginia 24061, United States
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9
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Lemkul JA. Same fold, different properties: polarizable molecular dynamics simulations of telomeric and TERRA G-quadruplexes. Nucleic Acids Res 2020; 48:561-575. [PMID: 31807754 PMCID: PMC6954416 DOI: 10.1093/nar/gkz1154] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/21/2019] [Accepted: 11/26/2019] [Indexed: 12/12/2022] Open
Abstract
DNA and RNA sequences rich in guanine can fold into noncanonical structures called G-quadruplexes (GQs), which exhibit a common stem structure of Hoogsteen hydrogen-bonded guanine tetrads and diverse loop structures. GQ sequence motifs are overrepresented in promoters, origins of replication, telomeres, and untranslated regions in mRNA, suggesting roles in modulating gene expression and preserving genomic integrity. Given these roles and unique aspects of different structures, GQs are attractive targets for drug design, but greater insight into GQ folding pathways and the interactions stabilizing them is required. Here, we performed molecular dynamics simulations to study two bimolecular GQs, a telomeric DNA GQ and the analogous telomeric repeat-containing RNA (TERRA) GQ. We applied the Drude polarizable force field, which we show outperforms the additive CHARMM36 force field in both ion retention and maintenance of the GQ folds. The polarizable simulations reveal that the GQs bind bulk K+ ions differently, and that the TERRA GQ accumulates more K+ ions, suggesting different ion interactions stabilize these structures. Nucleobase dipole moments vary as a function of position and also contribute to ion binding. Finally, we show that the TERRA GQ is more sensitive than the telomeric DNA GQ to water-mediated modulation of ion-induced dipole-dipole interactions.
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Affiliation(s)
- Justin A Lemkul
- Department of Biochemistry and Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061, USA
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10
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Molecular dynamics simulations of G-quadruplexes: The basic principles and their application to folding and ligand binding. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2020. [DOI: 10.1016/bs.armc.2020.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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11
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Jing Z, Liu C, Cheng SY, Qi R, Walker BD, Piquemal JP, Ren P. Polarizable Force Fields for Biomolecular Simulations: Recent Advances and Applications. Annu Rev Biophys 2019; 48:371-394. [PMID: 30916997 DOI: 10.1146/annurev-biophys-070317-033349] [Citation(s) in RCA: 223] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Realistic modeling of biomolecular systems requires an accurate treatment of electrostatics, including electronic polarization. Due to recent advances in physical models, simulation algorithms, and computing hardware, biomolecular simulations with advanced force fields at biologically relevant timescales are becoming increasingly promising. These advancements have not only led to new biophysical insights but also afforded opportunities to advance our understanding of fundamental intermolecular forces. This article describes the recent advances and applications, as well as future directions, of polarizable force fields in biomolecular simulations.
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Affiliation(s)
- Zhifeng Jing
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Chengwen Liu
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Sara Y Cheng
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Rui Qi
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Brandon D Walker
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
| | - Jean-Philip Piquemal
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA; .,Sorbonne Université, CNRS, Laboratoire de Chimie Theórique, 75252 Paris CEDEX 05, France.,Institut Universitaire de France, 75005 Paris, France
| | - Pengyu Ren
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA;
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12
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Salsbury AM, Lemkul JA. Molecular Dynamics Simulations of the c-kit1 Promoter G-Quadruplex: Importance of Electronic Polarization on Stability and Cooperative Ion Binding. J Phys Chem B 2018; 123:148-159. [DOI: 10.1021/acs.jpcb.8b11026] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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13
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The estimation of H-bond and metal ion-ligand interaction energies in the G-Quadruplex ⋯ Mn+ complexes. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.02.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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14
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Havrila M, Stadlbauer P, Islam B, Otyepka M, Šponer J. Effect of Monovalent Ion Parameters on Molecular Dynamics Simulations of G-Quadruplexes. J Chem Theory Comput 2017; 13:3911-3926. [PMID: 28657760 DOI: 10.1021/acs.jctc.7b00257] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
G-quadruplexes (GQs) are key noncanonical DNA and RNA architectures stabilized by desolvated monovalent cations present in their central channels. We analyze extended atomistic molecular dynamics simulations (∼580 μs in total) of GQs with 11 monovalent cation parametrizations, assessing GQ overall structural stability, dynamics of internal cations, and distortions of the G-tetrad geometries. Majority of simulations were executed with the SPC/E water model; however, test simulations with TIP3P and OPC water models are also reported. The identity and parametrization of ions strongly affect behavior of a tetramolecular d[GGG]4 GQ, which is unstable with several ion parametrizations. The remaining studied RNA and DNA GQs are structurally stable, though the G-tetrad geometries are always deformed by bifurcated H-bonding in a parametrization-specific manner. Thus, basic 10-μs-scale simulations of fully folded GQs can be safely done with a number of cation parametrizations. However, there are parametrization-specific differences and basic force-field errors affecting the quantitative description of ion-tetrad interactions, which may significantly affect studies of the ion-binding processes and description of the GQ folding landscape. Our d[GGG]4 simulations indirectly suggest that such studies will also be sensitive to the water models. During exchanges with bulk water, the Na+ ions move inside the GQs in a concerted manner, while larger relocations of the K+ ions are typically separated. We suggest that the Joung-Cheatham SPC/E K+ parameters represent a safe choice in simulation studies of GQs, though variation of ion parameters can be used for specific simulation goals.
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Affiliation(s)
- Marek Havrila
- Institute of Biophysics, Academy of Sciences of the Czech Republic , Královopolská 135, 612 65 Brno, Czech Republic.,CEITEC - Central European Institute of Technology, Masaryk University , Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Petr Stadlbauer
- Institute of Biophysics, Academy of Sciences of the Czech Republic , Královopolská 135, 612 65 Brno, Czech Republic.,Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University , 17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Barira Islam
- Institute of Biophysics, Academy of Sciences of the Czech Republic , Královopolská 135, 612 65 Brno, Czech Republic
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University , 17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Jiří Šponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic , Královopolská 135, 612 65 Brno, Czech Republic.,CEITEC - Central European Institute of Technology, Masaryk University , Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
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15
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Jin X, Zhang JZH, He X. Full QM Calculation of RNA Energy Using Electrostatically Embedded Generalized Molecular Fractionation with Conjugate Caps Method. J Phys Chem A 2017; 121:2503-2514. [PMID: 28264557 DOI: 10.1021/acs.jpca.7b00859] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In this study, the electrostatically embedded generalized molecular fractionation with conjugate caps (concaps) method (EE-GMFCC) was employed for efficient linear-scaling quantum mechanical (QM) calculation of total energies of RNAs. In the EE-GMFCC approach, the total energy of RNA is calculated by taking a proper combination of the QM energy of each nucleotide-centric fragment with large caps or small caps (termed EE-GMFCC-LC and EE-GMFCC-SC, respectively) deducted by the energies of concaps. The two-body QM interaction energy between non-neighboring ribonucleotides which are spatially in close contact are also taken into account for the energy calculation. Numerical studies were carried out to calculate the total energies of a number of RNAs using the EE-GMFCC-LC and EE-GMFCC-SC methods at levels of the Hartree-Fock (HF) method, density functional theory (DFT), and second-order many-body perturbation theory (MP2), respectively. The results show that the efficiency of the EE-GMFCC-SC method is about 3 times faster than the EE-GMFCC-LC method with minimal accuracy sacrifice. The EE-GMFCC-SC method is also applied for relative energy calculations of 20 different conformers of two RNA systems using HF and DFT, respectively. Both single-point and relative energy calculations demonstrate that the EE-GMFCC method has deviations from the full system results of only a few kcal/mol.
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Affiliation(s)
- Xinsheng Jin
- School of Chemistry and Molecular Engineering, East China Normal University , Shanghai 200062, China
| | - John Z H Zhang
- School of Chemistry and Molecular Engineering, East China Normal University , Shanghai 200062, China.,NYU-ECNU Center for Computational Chemistry at NYU Shanghai , Shanghai 200062, China.,Department of Chemistry, New York University , New York, New York 10003, United States
| | - Xiao He
- School of Chemistry and Molecular Engineering, East China Normal University , Shanghai 200062, China.,NYU-ECNU Center for Computational Chemistry at NYU Shanghai , Shanghai 200062, China
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16
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Šponer J, Bussi G, Stadlbauer P, Kührová P, Banáš P, Islam B, Haider S, Neidle S, Otyepka M. Folding of guanine quadruplex molecules-funnel-like mechanism or kinetic partitioning? An overview from MD simulation studies. Biochim Biophys Acta Gen Subj 2016; 1861:1246-1263. [PMID: 27979677 DOI: 10.1016/j.bbagen.2016.12.008] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 12/04/2016] [Accepted: 12/11/2016] [Indexed: 01/18/2023]
Abstract
BACKGROUND Guanine quadruplexes (GQs) play vital roles in many cellular processes and are of much interest as drug targets. In contrast to the availability of many structural studies, there is still limited knowledge on GQ folding. SCOPE OF REVIEW We review recent molecular dynamics (MD) simulation studies of the folding of GQs, with an emphasis paid to the human telomeric DNA GQ. We explain the basic principles and limitations of all types of MD methods used to study unfolding and folding in a way accessible to non-specialists. We discuss the potential role of G-hairpin, G-triplex and alternative GQ intermediates in the folding process. We argue that, in general, folding of GQs is fundamentally different from funneled folding of small fast-folding proteins, and can be best described by a kinetic partitioning (KP) mechanism. KP is a competition between at least two (but often many) well-separated and structurally different conformational ensembles. MAJOR CONCLUSIONS The KP mechanism is the only plausible way to explain experiments reporting long time-scales of GQ folding and the existence of long-lived sub-states. A significant part of the natural partitioning of the free energy landscape of GQs comes from the ability of the GQ-forming sequences to populate a large number of syn-anti patterns in their G-tracts. The extreme complexity of the KP of GQs typically prevents an appropriate description of the folding landscape using just a few order parameters or collective variables. GENERAL SIGNIFICANCE We reconcile available computational and experimental studies of GQ folding and formulate basic principles characterizing GQ folding landscapes. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio.
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Affiliation(s)
- Jiří Šponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic; Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic.
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, 34136 Trieste, Italy
| | - Petr Stadlbauer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic; Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Petra Kührová
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Pavel Banáš
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic
| | - Barira Islam
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Shozeb Haider
- UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Stephen Neidle
- UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic
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17
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Rebič M, Laaksonen A, Šponer J, Uličný J, Mocci F. Molecular Dynamics Simulation Study of Parallel Telomeric DNA Quadruplexes at Different Ionic Strengths: Evaluation of Water and Ion Models. J Phys Chem B 2016; 120:7380-91. [PMID: 27379924 DOI: 10.1021/acs.jpcb.6b06485] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Most molecular dynamics (MD) simulations of DNA quadruplexes have been performed under minimal salt conditions using the Åqvist potential parameters for the cation with the TIP3P water model. Recently, this combination of parameters has been reported to be problematic for the stability of quadruplex DNA, especially caused by the ion interactions inside or near the quadruplex channel. Here, we verify how the choice of ion parameters and water model can affect the quadruplex structural stability and the interactions with the ions outside the channel. We have performed a series of MD simulations of the human full-parallel telomeric quadruplex by neutralizing its negative charge with K(+) ions. Three combinations of different cation potential parameters and water models have been used: (a) Åqvist ion parameters, TIP3P water model; (b) Joung and Cheatham ion parameters, TIP3P water model; and (c) Joung and Cheatham ion parameters, TIP4Pew water model. For the combinations (b) and (c), the effect of the ionic strength has been evaluated by adding increasing amounts of KCl salt (50, 100, and 200 mM). Two independent simulations using the Åqvist parameters with the TIP3P model show that this combination is clearly less suited for the studied quadruplex with K(+) as counterions. In both simulations, one ion escapes from the channel, followed by significant deformation of the structure, leading to deviating conformation compared to that in the reference crystallographic data. For the other combinations of ion and water potentials, no tendency is observed for the channel ions to escape from the quadruplex channel. In addition, the internal mobility of the three loops, torsion angles, and counterion affinity have been investigated at varied salt concentrations. In summary, the selection of ion and water models is crucial as it can affect both the structure and dynamics as well as the interactions of the quadruplex with its counterions. The results obtained with the TIP4Pew model are found to be closest to the experimental data at all of the studied ion concentrations.
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Affiliation(s)
- Matúš Rebič
- Department of Materials and Environmental Chemistry, Division of Physical Chemistry, Arrhenius Laboratory, Stockholm University , 10691 Stockholm, Sweden.,Science for Life Laboratory (SciLifelab) , 17121 Solna, Sweden
| | - Aatto Laaksonen
- Department of Materials and Environmental Chemistry, Division of Physical Chemistry, Arrhenius Laboratory, Stockholm University , 10691 Stockholm, Sweden.,Science for Life Laboratory (SciLifelab) , 17121 Solna, Sweden.,Stellenbosch Institute of Advanced Study (STIAS), Wallenberg Research Centre at Stellenbosch University , 7600 Stellenbosch, South Africa.,Department of Chemical and Geological Sciences, University of Cagliari , I-09042 Monserrato, Italy
| | - Jiří Šponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic (AVČR) , Kralovopolska 135, 612 65 Brno, Czech Republic.,Central European Institute of Technology (CEITEC) , Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | | | - Francesca Mocci
- Department of Materials and Environmental Chemistry, Division of Physical Chemistry, Arrhenius Laboratory, Stockholm University , 10691 Stockholm, Sweden.,Science for Life Laboratory (SciLifelab) , 17121 Solna, Sweden.,Department of Chemical and Geological Sciences, University of Cagliari , I-09042 Monserrato, Italy
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18
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Askerka M, Ho J, Batista ER, Gascón JA, Batista VS. The MOD-QM/MM Method: Applications to Studies of Photosystem II and DNA G-Quadruplexes. Methods Enzymol 2016; 577:443-81. [PMID: 27498648 PMCID: PMC5304415 DOI: 10.1016/bs.mie.2016.05.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2024]
Abstract
Quantum mechanics/molecular mechanics (QM/MM) hybrid methods are currently the most powerful computational tools for studies of structure/function relations and catalytic sites embedded in macrobiomolecules (eg, proteins and nucleic acids). QM/MM methodologies are highly efficient since they implement quantum chemistry methods for modeling only the portion of the system involving bond-breaking/forming processes (QM layer), as influenced by the surrounding molecular environment described in terms of molecular mechanics force fields (MM layer). Some of the limitations of QM/MM methods when polarization effects are not explicitly considered include the approximate treatment of electrostatic interactions between QM and MM layers. Here, we review recent advances in the development of computational protocols that allow for rigorous modeling of electrostatic interactions in biomacromolecules and structural refinement, beyond the common limitations of QM/MM hybrid methods. We focus on photosystem II (PSII) with emphasis on the description of the oxygen-evolving complex (OEC) and its high-resolution extended X-ray absorption fine structure spectra (EXAFS) in conjunction with Monte Carlo structural refinement. Furthermore, we review QM/MM structural refinement studies of DNA G4 quadruplexes with embedded monovalent cations and direct comparisons to NMR data.
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Affiliation(s)
- M Askerka
- Yale University, New Haven, CT, United States
| | - J Ho
- Yale University, New Haven, CT, United States
| | - E R Batista
- Los Alamos National Laboratory, Los Alamos, NM, United States
| | - J A Gascón
- University of Connecticut, Storrs, CT, United States
| | - V S Batista
- Yale University, New Haven, CT, United States.
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19
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Luo D, Mu Y. Computational Insights into the Stability and Folding Pathways of Human Telomeric DNA G-Quadruplexes. J Phys Chem B 2016; 120:4912-26. [DOI: 10.1021/acs.jpcb.6b01919] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Di Luo
- School
of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Yuguang Mu
- School
of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
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20
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Gkionis K, Kruse H, Šponer J. Derivation of Reliable Geometries in QM Calculations of DNA Structures: Explicit Solvent QM/MM and Restrained Implicit Solvent QM Optimizations of G-Quadruplexes. J Chem Theory Comput 2016; 12:2000-16. [DOI: 10.1021/acs.jctc.5b01025] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Konstantinos Gkionis
- Institute of Biophysics,
Academy of Sciences of the Czech Republic, Královopolská 135, 612
65 Brno, Czech Republic
| | - Holger Kruse
- Institute of Biophysics,
Academy of Sciences of the Czech Republic, Královopolská 135, 612
65 Brno, Czech Republic
| | - Jiří Šponer
- Institute of Biophysics,
Academy of Sciences of the Czech Republic, Královopolská 135, 612
65 Brno, Czech Republic
- CEITEC
− Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
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21
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Nikolaienko TY, Bulavin LA, Hovorun DM. Can we treat ab initio atomic charges and bond orders as conformation-independent electronic structure descriptors? RSC Adv 2016. [DOI: 10.1039/c6ra17055b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
It is shown that atomic charges and bond orders of 2′-deoxycytidine depend on the molecule conformation.
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Affiliation(s)
- T. Yu. Nikolaienko
- Taras Shevchenko National University of Kyiv
- Faculty of Physics
- Kyiv 01601
- Ukraine
| | - L. A. Bulavin
- Taras Shevchenko National University of Kyiv
- Faculty of Physics
- Kyiv 01601
- Ukraine
| | - D. M. Hovorun
- Department of Molecular and Quantum Biophysics
- Institute of Molecular Biology and Genetics
- National Academy of Sciences of Ukraine
- Kyiv 03680
- Ukraine
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22
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Jin X, Zhu T, Zhang JZH, He X. A systematic study on RNA NMR chemical shift calculation based on the automated fragmentation QM/MM approach. RSC Adv 2016. [DOI: 10.1039/c6ra22518g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
1H, 13C and 15N NMR chemical shift calculations on RNAs were performed using the automated fragmentation quantum mechanics/molecular mechanics (AF-QM/MM) approach.
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Affiliation(s)
- Xinsheng Jin
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Tong Zhu
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
- NYU-ECNU Center for Computational Chemistry
| | - John Z. H. Zhang
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
- NYU-ECNU Center for Computational Chemistry
| | - Xiao He
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
- NYU-ECNU Center for Computational Chemistry
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23
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Swails J, Zhu T, He X, Case DA. AFNMR: automated fragmentation quantum mechanical calculation of NMR chemical shifts for biomolecules. JOURNAL OF BIOMOLECULAR NMR 2015; 63:125-39. [PMID: 26232926 PMCID: PMC6556433 DOI: 10.1007/s10858-015-9970-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 07/20/2015] [Indexed: 05/08/2023]
Abstract
We evaluate the performance of the automated fragmentation quantum mechanics/molecular mechanics approach (AF-QM/MM) on the calculation of protein and nucleic acid NMR chemical shifts. The AF-QM/MM approach models solvent effects implicitly through a set of surface charges computed using the Poisson-Boltzmann equation, and it can also be combined with an explicit solvent model through the placement of water molecules in the first solvation shell around the solute; the latter substantially improves the accuracy of chemical shift prediction of protons involved in hydrogen bonding with solvent. We also compare the performance of AF-QM/MM on proteins and nucleic acids with two leading empirical chemical shift prediction programs SHIFTS and SHIFTX2. Although the empirical programs outperform AF-QM/MM in predicting chemical shifts, the differences are in some cases small, and the latter can be applied to chemical shifts on biomolecules which are outside the training set employed by the empirical programs, such as structures containing ligands, metal centers, and non-standard residues. The AF-QM/MM described here is implemented in version 5 of the SHIFTS software, and is fully automated, so that only a structure in PDB format is required as input.
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Affiliation(s)
- Jason Swails
- Department of Chemistry and Chemical Biology and BioMaPS Institute, Rutgers University, Piscataway, NJ, 08854, USA
| | - Tong Zhu
- State Key Laboratory of Precision Spectroscopy, Institute of Theoretical and Computational Science, East China Normal University, Shanghai, 200062, China
| | - Xiao He
- State Key Laboratory of Precision Spectroscopy, Institute of Theoretical and Computational Science, East China Normal University, Shanghai, 200062, China.
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai, 200062, China.
| | - David A Case
- Department of Chemistry and Chemical Biology and BioMaPS Institute, Rutgers University, Piscataway, NJ, 08854, USA.
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24
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Islam B, Stadlbauer P, Krepl M, Koca J, Neidle S, Haider S, Sponer J. Extended molecular dynamics of a c-kit promoter quadruplex. Nucleic Acids Res 2015; 43:8673-93. [PMID: 26245347 PMCID: PMC4605300 DOI: 10.1093/nar/gkv785] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 07/21/2015] [Indexed: 01/29/2023] Open
Abstract
The 22-mer c-kit promoter sequence folds into a parallel-stranded quadruplex with a unique structure, which has been elucidated by crystallographic and NMR methods and shows a high degree of structural conservation. We have carried out a series of extended (up to 10 μs long, ∼50 μs in total) molecular dynamics simulations to explore conformational stability and loop dynamics of this quadruplex. Unfolding no-salt simulations are consistent with a multi-pathway model of quadruplex folding and identify the single-nucleotide propeller loops as the most fragile part of the quadruplex. Thus, formation of propeller loops represents a peculiar atomistic aspect of quadruplex folding. Unbiased simulations reveal μs-scale transitions in the loops, which emphasizes the need for extended simulations in studies of quadruplex loops. We identify ion binding in the loops which may contribute to quadruplex stability. The long lateral-propeller loop is internally very stable but extensively fluctuates as a rigid entity. It creates a size-adaptable cleft between the loop and the stem, which can facilitate ligand binding. The stability gain by forming the internal network of GA base pairs and stacks of this loop may be dictating which of the many possible quadruplex topologies is observed in the ground state by this promoter quadruplex.
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Affiliation(s)
- Barira Islam
- Central European Institute of Technology (CEITEC), Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Petr Stadlbauer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Miroslav Krepl
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Jaroslav Koca
- Central European Institute of Technology (CEITEC), Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic National Center for Biomolecular Research, Faculty of Science, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Stephen Neidle
- UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Shozeb Haider
- UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK
| | - Jiri Sponer
- Central European Institute of Technology (CEITEC), Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic
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25
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Bazzi S, Novotný J, Yurenko YP, Marek R. Designing a New Class of Bases for Nucleic Acid Quadruplexes and Quadruplex-Active Ligands. Chemistry 2015; 21:9414-25. [PMID: 26032561 DOI: 10.1002/chem.201500743] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Indexed: 01/13/2023]
Abstract
A new class of quadruplex nucleobases, derived from 3-deazaguanine, has been designed for various applications as smart quadruplex ligands as well as quadruplex-based aptamers, receptors, and sensors. An efficient strategy for modifying the guanine quadruplex core has been developed and tested by using quantum chemistry methods. Several potential guanine derivatives modified at the 3- or 8-position or both are analyzed, and the results compared to reference systems containing natural guanine. Analysis of the formation energies (BLYP-D3(BJ)/def2-TZVPP level of theory, in combination with the COSMO model for water) in model systems consisting of two and three stacked tetrads with Na(+) /K(+) ion(s) inside the internal channel indicates that the formation of structures with 3-halo-3-deazaguanine bases leads to a substantial gain in energy, as compared to the corresponding reference guanine complexes. The results cast light on changes in the noncovalent interactions (hydrogen bonding, stacking, and ion coordination) in a quadruplex stem upon modification of the guanine core. In particular, the enhanced stability of the modified quadruplexes was shown to originate mainly from increased π-π stacking. Our study suggests the 3-halo-3-deazaguanine skeleton as a potential building unit for quadruplex systems and smart G-quadruplex ligands.
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Affiliation(s)
- Sophia Bazzi
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic).,National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic)
| | - Jan Novotný
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic)
| | - Yevgen P Yurenko
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic)
| | - Radek Marek
- CEITEC-Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic). .,National Center for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno (Czech Republic).
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26
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Ho J, Newcomer MB, Ragain CM, Gascon JA, Batista ER, Loria JP, Batista VS. MoD-QM/MM Structural Refinement Method: Characterization of Hydrogen Bonding in the Oxytricha nova G-Quadruplex. J Chem Theory Comput 2014; 10:5125-35. [PMID: 26584390 PMCID: PMC5304451 DOI: 10.1021/ct500571k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A generalization of the Moving-Domain Quantum Mechanics/Molecular Mechanics (MoD-QM/MM) hybrid method [Gascon, J. A.; Leung, S. S. F.; Batista, E. R.; Batista, V. S. J. Chem. Theory Comput. 2006, 2, 175-186] is introduced to provide a self-consistent computational protocol for structural refinement of extended systems. The method partitions the system into molecular domains that are iteratively optimized as quantum mechanical (QM) layers embedded in their surrounding molecular environment to obtain an ab initio quality description of the geometry and the molecular electrostatic potential of the extended system composed of those constituent fragments. The resulting methodology is benchmarked as applied to model systems that allow for full QM optimization as well as through refinement of the hydrogen bonding geometry in Oxytricha nova guanine quadruplex for which several studies have been reported, including the X-ray structure and NMR data. Calculations of (1)H NMR chemical shifts based on the gauge independent atomic orbital (GIAO) method and direct comparisons with experiments show that solvated MoD-QM/MM structures, sampled from explicit solvent molecular dynamics simulations, allow for NMR simulations in much improved agreement with experimental data than models based on the X-ray structure or those optimized using classical molecular mechanics force fields.
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Affiliation(s)
- Junming Ho
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Michael B. Newcomer
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Christina M. Ragain
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Jose A. Gascon
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Enrique R. Batista
- Theoretical Division, Los Alamos National Laboratory, MS-B214, Los Alamos, New Mexico 87545, United States
| | - J. Patrick Loria
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Victor S. Batista
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
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27
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Triplex intermediates in folding of human telomeric quadruplexes probed by microsecond-scale molecular dynamics simulations. Biochimie 2014; 105:22-35. [DOI: 10.1016/j.biochi.2014.07.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Accepted: 07/01/2014] [Indexed: 11/23/2022]
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28
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Lu S, Huang W, Zhang J. Recent computational advances in the identification of allosteric sites in proteins. Drug Discov Today 2014; 19:1595-600. [PMID: 25107670 DOI: 10.1016/j.drudis.2014.07.012] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 07/10/2014] [Accepted: 07/30/2014] [Indexed: 01/08/2023]
Abstract
Allosteric modulators have the potential to fine-tune protein functional activity. Therefore, the targeting of allosteric sites, as a strategy in drug design, is gaining increasing attention. Currently, it is not trivial to find and characterize new allosteric sites by experimental approaches. Alternatively, computational approaches are useful in helping researchers analyze and select potential allosteric sites for drug discovery. Here, we review state-of-the-art computational approaches directed at predicting putative allosteric sites in proteins, along with examples of successes in identifying allosteric sites utilizing these methods. We also discuss the challenges in developing reliable methods for predicting allosteric sites and tactics to resolve demanding tasks.
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Affiliation(s)
- Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai 200025, China
| | - Wenkang Huang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai 200025, China
| | - Jian Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai JiaoTong University, School of Medicine (SJTU-SM), Shanghai 200025, China.
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29
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Gkionis K, Kruse H, Platts JA, Mládek A, Koča J, Šponer J. Ion Binding to Quadruplex DNA Stems. Comparison of MM and QM Descriptions Reveals Sizable Polarization Effects Not Included in Contemporary Simulations. J Chem Theory Comput 2014; 10:1326-40. [DOI: 10.1021/ct4009969] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Konstantinos Gkionis
- CEITEC
- Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Holger Kruse
- CEITEC
- Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - James A. Platts
- School
of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, United Kingdom
| | - Arnošt Mládek
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská
135, 612 65 Brno, Czech Republic
| | - Jaroslav Koča
- CEITEC
- Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jiří Šponer
- CEITEC
- Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská
135, 612 65 Brno, Czech Republic
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Šponer J, Mládek A, Špačková N, Cang X, Cheatham TE, Grimme S. Relative stability of different DNA guanine quadruplex stem topologies derived using large-scale quantum-chemical computations. J Am Chem Soc 2013; 135:9785-96. [PMID: 23742743 PMCID: PMC3775466 DOI: 10.1021/ja402525c] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We provide theoretical predictions of the intrinsic stability of different arrangements of guanine quadruplex (G-DNA) stems. Most computational studies of nucleic acids have applied Molecular Mechanics (MM) approaches using simple pairwise-additive force fields. The principle limitation of such calculations is the highly approximate nature of the force fields. In this study, we for the first time apply accurate QM computations (DFT-D3 with large atomic orbital basis sets) to essentially complete DNA building blocks, seven different folds of the cation-stabilized two-quartet G-DNA stem, each having more than 250 atoms. The solvent effects are approximated by COSMO continuum solvent. We reveal sizable differences between MM and QM descriptions of relative energies of different G-DNA stems, which apparently reflect approximations of the DNA force field. Using the QM energy data, we propose correction to earlier free energy estimates of relative stabilities of different parallel, hybrid, and antiparallel G-stem folds based on classical simulations. The new energy ranking visibly improves the agreement between theory and experiment. We predict the 5'-anti-anti-3' GpG dinucleotide step to be the most stable one, closely followed by the 5'-syn-anti-3' step. The results are in good agreement with known experimental structures of 2-, 3-, and 4-quartet G-DNA stems. Besides providing specific results for G-DNA, our study highlights basic limitations of force field modeling of nucleic acids. Although QM computations have their own limitations, mainly the lack of conformational sampling and the approximate description of the solvent, they can substantially improve the quality of calculations currently relying exclusively on force fields.
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Affiliation(s)
- Jiří Šponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65 Brno, Czech Republic
- CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Arnošt Mládek
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65 Brno, Czech Republic
- CEITEC - Central European Institute of Technology, Masaryk University, Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Nad’a Špačková
- Institute of Biophysics, Academy of Sciences of the Czech Republic, Královopolská 135, 612 65 Brno, Czech Republic
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic
| | - Xiaohui Cang
- Institute of Genetics, School of Life Science, Zhejiang University, Hangzhou, China 310058
| | - Thomas E. Cheatham
- Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, UT 84124, USA
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institute of Physical & Theoretical Chemistry, University of Bonn, Beringstrasse. 4, D-53115 Bonn, Germany
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