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Zeng Y, Pavlova A, Nelson PM, Glick ZL, Yang L, Pang YT, Spivak M, Licari G, Tajkhorshid E, Sherrill CD, Gumbart JC. Broadening access to small-molecule parameterization with the force field toolkit. J Chem Phys 2024; 160:242501. [PMID: 38916266 DOI: 10.1063/5.0196848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 05/27/2024] [Indexed: 06/26/2024] Open
Abstract
Access to accurate force-field parameters for small molecules is crucial for computational studies of their interactions with proteins. Although a number of general force fields for small molecules exist, e.g., CGenFF, GAFF, and OPLS, they do not cover all common chemical groups and their combinations. The Force Field Toolkit (ffTK) provides a comprehensive graphical interface that streamlines the development of classical parameters for small molecules directly from quantum mechanical (QM) calculations, allowing for force-field generation for almost any chemical group and validation of the fit relative to the target data. ffTK relies on supported external software for the QM calculations, but it can generate the necessary QM input files and parse and analyze the QM output. In previous ffTK versions, support for Gaussian and ORCA QM packages was implemented. Here, we add support for Psi4, an open-source QM package free for all users, thereby broadening user access to ffTK. We also compare the parameter sets obtained with the new ffTK version using Gaussian, ORCA, and Psi4 for three molecules: pyrrolidine, n-propylammonium cation, and chlorobenzene. Despite minor differences between the resulting parameter sets for each compound, most prominently in the dihedral and improper terms, we show that conformational distributions sampled in molecular dynamics simulations using these parameter sets are quite comparable.
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Affiliation(s)
- Yunlin Zeng
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Anna Pavlova
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Philip M Nelson
- Center for Computational Molecular Science and Technology, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Zachary L Glick
- Center for Computational Molecular Science and Technology, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Lan Yang
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Yui Tik Pang
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Mariano Spivak
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Giuseppe Licari
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Emad Tajkhorshid
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Biochemistry and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - C David Sherrill
- Center for Computational Molecular Science and Technology, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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Bouchouireb Z, Thany SH, Le Questel JY. Development of CHARMM compatible force field parameters and molecular dynamics simulations for the pesticide flupyradifurone. J Comput Chem 2024; 45:377-391. [PMID: 37966816 DOI: 10.1002/jcc.27245] [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] [Received: 07/09/2023] [Revised: 10/09/2023] [Accepted: 10/11/2023] [Indexed: 11/16/2023]
Abstract
Flupyradifurone (FLU) is a novel butenolide insecticide with partial agonist activity for insect nicotinic acetylcholine receptors. Its safety for non-target organisms has been questioned in the literature, despite initial claims of its harmlessness. Detailed understanding of its toxicity and related molecular mechanisms remain under discussion. Thus, in this work, an optimized set of CHARMM compatible parameters for FLU is presented. CHARMM General Force Field program was used as a starting point while the non-bonded and bonded parameters were adjusted and optimized to reproduce MP2/6-31G(d) accuracy level results. For the validity assessment of these parameters, infrared spectrum, water-octanol partition coefficient, and normal modes were computed and compared to experimental values found in the literature. Several MD simulations of FLU in water and FLU in complex with an acetylcholine-binding protein were performed to estimate the ability of the optimized parameters to correctly describe its torsional space and reproduce observed crystallographic trends respectively.
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Affiliation(s)
| | - Steeve H Thany
- Université d'Orléans, LBLGC USC INRAE 1328, Orléans, France
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Spivak M, Stone JE, Ribeiro J, Saam J, Freddolino PL, Bernardi RC, Tajkhorshid E. VMD as a Platform for Interactive Small Molecule Preparation and Visualization in Quantum and Classical Simulations. J Chem Inf Model 2023; 63:4664-4678. [PMID: 37506321 PMCID: PMC10516160 DOI: 10.1021/acs.jcim.3c00658] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Modeling and simulation of small molecules such as drugs and biological cofactors have been both a major focus of computational chemistry for decades and a growing need among computational biophysicists who seek to investigate the interaction of different types of ligands with biomolecules. Of particular interest in this regard are quantum mechanical (QM) calculations that are used to more accurately describe such small molecules, which can be of heterogeneous structures and chemistry, either in purely QM calculations or in hybrid QM/molecular mechanics (MM) simulations. QM programs are also used to develop MM force field parameters for small molecules to be used along with established force fields for biomolecules in classical simulations. With this growing need in mind, here we report a set of software tools developed and closely integrated within the broadly used molecular visualization/analysis program, VMD, that allow the user to construct, modify, and parametrize small molecules and prepare them for QM, hybrid QM/MM, or classical simulations. The tools also provide interactive analysis and visualization capabilities in an easy-to-use and integrated environment. In this paper, we briefly report on these tools and their major features and capabilities, along with examples of how they can facilitate molecular research in computational biophysics that might be otherwise prohibitively complex.
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Affiliation(s)
- Mariano Spivak
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - John E Stone
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - João Ribeiro
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Jan Saam
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Peter L Freddolino
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Rafael C Bernardi
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Physics, Auburn University, Auburn, Alabama 36849, United States
| | - Emad Tajkhorshid
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Biochemistry, Center for Biophyics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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Grohs L, Cheng L, Cönen S, Haddad BG, Bülow A, Toklucu I, Ernst L, Körner J, Schmalzing G, Lampert A, Machtens JP, Hausmann R. Diclofenac and other non-steroidal anti-inflammatory drugs (NSAIDs) are competitive antagonists of the human P2X3 receptor. Front Pharmacol 2023; 14:1120360. [PMID: 37007008 PMCID: PMC10060569 DOI: 10.3389/fphar.2023.1120360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/24/2023] [Indexed: 03/18/2023] Open
Abstract
Introduction: The P2X3 receptor (P2X3R), an ATP-gated non-selective cation channel of the P2X receptor family, is expressed in sensory neurons and involved in nociception. P2X3R inhibition was shown to reduce chronic and neuropathic pain. In a previous screening of 2000 approved drugs, natural products, and bioactive substances, various non-steroidal anti-inflammatory drugs (NSAIDs) were found to inhibit P2X3R-mediated currents.Methods: To investigate whether the inhibition of P2X receptors contributes to the analgesic effect of NSAIDs, we characterized the potency and selectivity of various NSAIDs at P2X3R and other P2XR subtypes using two-electrode voltage clamp electrophysiology.Results: We identified diclofenac as a hP2X3R and hP2X2/3R antagonist with micromolar potency (with IC50 values of 138.2 and 76.7 µM, respectively). A weaker inhibition of hP2X1R, hP2X4R, and hP2X7R by diclofenac was determined. Flufenamic acid (FFA) inhibited hP2X3R, rP2X3R, and hP2X7R (IC50 values of 221 µM, 264.1 µM, and ∼900 µM, respectively), calling into question its use as a non-selective ion channel blocker, when P2XR-mediated currents are under study. Inhibition of hP2X3R or hP2X2/3R by diclofenac could be overcome by prolonged ATP application or increasing concentrations of the agonist α,β-meATP, respectively, indicating competition of diclofenac and the agonists. Molecular dynamics simulation showed that diclofenac largely overlaps with ATP bound to the open state of the hP2X3R. Our results suggest a competitive antagonism through which diclofenac, by interacting with residues of the ATP-binding site, left flipper, and dorsal fin domains, inhibits the gating of P2X3R by conformational fixation of the left flipper and dorsal fin domains. In summary, we demonstrate the inhibition of the human P2X3 receptor by various NSAIDs. Diclofenac proved to be the most effective antagonist with a strong inhibition of hP2X3R and hP2X2/3R and a weaker inhibition of hP2X1R, hP2X4R, and hP2X7R.Discussion: Considering their involvement in nociception, inhibition of hP2X3R and hP2X2/3R by micromolar concentrations of diclofenac, which are rarely reached in the therapeutic range, may play a minor role in analgesia compared to the high-potency cyclooxygenase inhibition but may explain the known side effect of taste disturbances caused by diclofenac.
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Affiliation(s)
- Laura Grohs
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Department of Neurology, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Linhan Cheng
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
| | - Saskia Cönen
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Molecular and Cellular Physiology (IBI-1), Institute of Biological Information Processing (IBI), Forschungszentrum Jülich, Jülich, Germany
| | - Bassam G. Haddad
- Molecular and Cellular Physiology (IBI-1), Institute of Biological Information Processing (IBI), Forschungszentrum Jülich, Jülich, Germany
| | - Astrid Bülow
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Department of Plastic Surgery, Hand Surgery—Burn Center, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Idil Toklucu
- Institute of Physiology (Neurophysiology), RWTH Aachen University, Aachen, Germany
| | - Lisa Ernst
- Institute for Laboratory Animal Science and Experimental Surgery, RWTH Aachen University, Aachen, Germany
| | - Jannis Körner
- Institute of Physiology (Neurophysiology), RWTH Aachen University, Aachen, Germany
- Department of Anesthesiology, University Hospital, RWTH Aachen University, Aachen, Germany
| | - Günther Schmalzing
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
| | - Angelika Lampert
- Institute of Physiology (Neurophysiology), RWTH Aachen University, Aachen, Germany
| | - Jan-Philipp Machtens
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- Molecular and Cellular Physiology (IBI-1), Institute of Biological Information Processing (IBI), Forschungszentrum Jülich, Jülich, Germany
| | - Ralf Hausmann
- Institute of Clinical Pharmacology, RWTH Aachen University, Aachen, Germany
- *Correspondence: Ralf Hausmann,
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Chen XR, Poudel L, Hong Z, Johnen P, Katti S, Tripathi A, Nile AH, Green SM, Khan D, Schaaf G, Bono F, Bankaitis VA, Igumenova TI. Mechanisms by which small molecules of diverse chemotypes arrest Sec14 lipid transfer activity. J Biol Chem 2023; 299:102861. [PMID: 36603766 PMCID: PMC9898755 DOI: 10.1016/j.jbc.2022.102861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 12/27/2022] [Accepted: 12/28/2022] [Indexed: 01/04/2023] Open
Abstract
Phosphatidylinositol (PtdIns) transfer proteins (PITPs) enhance the activities of PtdIns 4-OH kinases that generate signaling pools of PtdIns-4-phosphate. In that capacity, PITPs serve as key regulators of lipid signaling in eukaryotic cells. Although the PITP phospholipid exchange cycle is the engine that stimulates PtdIns 4-OH kinase activities, the underlying mechanism is not understood. Herein, we apply an integrative structural biology approach to investigate interactions of the yeast PITP Sec14 with small-molecule inhibitors (SMIs) of its phospholipid exchange cycle. Using a combination of X-ray crystallography, solution NMR spectroscopy, and atomistic MD simulations, we dissect how SMIs compete with native Sec14 phospholipid ligands and arrest phospholipid exchange. Moreover, as Sec14 PITPs represent new targets for the development of next-generation antifungal drugs, the structures of Sec14 bound to SMIs of diverse chemotypes reported in this study will provide critical information required for future structure-based design of next-generation lead compounds directed against Sec14 PITPs of virulent fungi.
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Affiliation(s)
- Xiao-Ru Chen
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas USA
| | - Lokendra Poudel
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas USA
| | - Zebin Hong
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Philipp Johnen
- Institute for Crop Science and Resource Conservation, Universität Bonn, Bonn, Germany
| | - Sachin Katti
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas USA
| | - Ashutosh Tripathi
- Department of Cell Biology & Genetics, Texas A&M University, College Station, Texas, USA
| | - Aaron H Nile
- Department of Cell Biology & Genetics, Texas A&M University, College Station, Texas, USA
| | - Savana M Green
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas USA; Department of Cell Biology & Genetics, Texas A&M University, College Station, Texas, USA
| | - Danish Khan
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas USA
| | - Gabriel Schaaf
- Institute for Crop Science and Resource Conservation, Universität Bonn, Bonn, Germany
| | - Fulvia Bono
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Vytas A Bankaitis
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas USA; Department of Cell Biology & Genetics, Texas A&M University, College Station, Texas, USA.
| | - Tatyana I Igumenova
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas USA.
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Wu Q, Huang T, Xia S, Otto F, Lee TY, Huang HD, Chiang YC. On the force field optimisation of [Formula: see text]-lactam cores using the force field Toolkit. J Comput Aided Mol Des 2022; 36:537-547. [PMID: 35819650 PMCID: PMC9399072 DOI: 10.1007/s10822-022-00464-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 06/21/2022] [Indexed: 11/29/2022]
Abstract
When employing molecular dynamics (MD) simulations for computer-aided drug design, the quality of the used force fields is highly important. Here we present reparametrisations of the force fields for the core molecules from 9 different [Formula: see text]-lactam classes, for which we utilized the force field Toolkit and Gaussian calculations. We focus on the parametrisation of the dihedral angles, with the goal of reproducing the optimised quantum geometry in MD simulations. Parameters taken from CGenFF turn out to be a good initial guess for the multiplicity of each dihedral angle, but the key to a successful parametrisation is found to lie in the phase shifts. Based on the optimised quantum geometry, we come up with a strategy for predicting the phase shifts prior to the dihedral potential fitting. This allows us to successfully parameterise 8 out of the 11 molecules studied here, while the remaining 3 molecules can also be parameterised with small adjustments. Our work highlights the importance of predicting the dihedral phase shifts in the ligand parametrisation protocol, and provides a simple yet valuable strategy for improving the process of parameterising force fields of drug-like molecules.
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Affiliation(s)
- Qiyang Wu
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen, 518172, China
| | - Tianyang Huang
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen, 518172, China
| | - Songyan Xia
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen, 518172, China
| | - Frank Otto
- Department of Chemistry, University College London, London, WC1H 0AJ, UK
| | - Tzong-Yi Lee
- Warshel Institute for Computational Biology, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen, 518172, China
| | - Hsien-Da Huang
- Warshel Institute for Computational Biology, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen, 518172, China
| | - Ying-Chih Chiang
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong (Shenzhen), Shenzhen, 518172, China.
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Pérez-Segura C, Goh BC, Hadden-Perilla JA. All-Atom MD Simulations of the HBV Capsid Complexed with AT130 Reveal Secondary and Tertiary Structural Changes and Mechanisms of Allostery. Viruses 2021; 13:564. [PMID: 33810481 PMCID: PMC8065791 DOI: 10.3390/v13040564] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/15/2021] [Accepted: 03/23/2021] [Indexed: 12/18/2022] Open
Abstract
The hepatitis B virus (HBV) capsid is an attractive drug target, relevant to combating viral hepatitis as a major public health concern. Among small molecules known to interfere with capsid assembly, the phenylpropenamides, including AT130, represent an important antiviral paradigm based on disrupting the timing of genome packaging. Here, all-atom molecular dynamics simulations of an intact AT130-bound HBV capsid reveal that the compound increases spike flexibility and improves recovery of helical secondary structure in the spike tips. Regions of the capsid-incorporated dimer that undergo correlated motion correspond to established sub-domains that pivot around the central chassis. AT130 alters patterns of correlated motion and other essential dynamics. A new conformational state of the dimer is identified, which can lead to dramatic opening of the intradimer interface and disruption of communication within the spike tip. A novel salt bridge is also discovered, which can mediate contact between the spike tip and fulcrum even in closed conformations, revealing a mechanism of direct communication across these sub-domains. Altogether, results describe a dynamical connection between the intra- and interdimer interfaces and enable mapping of allostery traversing the entire core protein dimer.
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Affiliation(s)
- Carolina Pérez-Segura
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA;
| | - Boon Chong Goh
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-Massachusetts Institute of Technology Alliance for Research and Technology Centre, Singapore 138602, Singapore;
| | - Jodi A. Hadden-Perilla
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA;
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Brooks CL, Case DA, Plimpton S, Roux B, van der Spoel D, Tajkhorshid E. Classical molecular dynamics. J Chem Phys 2021; 154:100401. [DOI: 10.1063/5.0045455] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Charles L. Brooks
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - David A. Case
- Department of Chemistry and Chemical Biology, Rutgers University, New Brunswick, New Jersey 08854, USA
| | - Steve Plimpton
- Computational Multiscale Department, Sandia National Laboratories, Albuquerque, New Mexico 87185-1316, USA
| | - Benoît Roux
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, USA
| | - David van der Spoel
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - Emad Tajkhorshid
- NIH Center for Macromolecular Modeling and Bioinformatics, Theoretical and Computational Biophysics Group, Beckman Institute for Advanced Science and Technology, Department of Biochemistry, and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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