1
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Antila HS, Dixit S, Kav B, Madsen JJ, Miettinen MS, Ollila OHS. Evaluating Polarizable Biomembrane Simulations against Experiments. J Chem Theory Comput 2024; 20:4325-4337. [PMID: 38718349 PMCID: PMC11137822 DOI: 10.1021/acs.jctc.3c01333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 04/10/2024] [Accepted: 04/10/2024] [Indexed: 05/29/2024]
Abstract
Owing to the increase of available computational capabilities and the potential for providing a more accurate description, polarizable molecular dynamics force fields are gaining popularity in modeling biomolecular systems. It is, however, crucial to evaluate how much precision is truly gained with increasing cost and complexity of the simulation. Here, we leverage the NMRlipids open collaboration and Databank to assess the performance of available polarizable lipid models─the CHARMM-Drude and the AMOEBA-based parameters─against high-fidelity experimental data and compare them to the top-performing nonpolarizable models. While some improvement in the description of ion binding to membranes is observed in the most recent CHARMM-Drude parameters, and the conformational dynamics of AMOEBA-based parameters are excellent, the best nonpolarizable models tend to outperform their polarizable counterparts for each property we explored. The identified shortcomings range from inaccuracies in describing the conformational space of lipids to excessively slow conformational dynamics. Our results provide valuable insights for the further refinement of polarizable lipid force fields and for selecting the best simulation parameters for specific applications.
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Affiliation(s)
- Hanne S. Antila
- Department
of Theory and Bio-Systems, Max Planck Institute
of Colloids and Interfaces, Potsdam 14476, Germany
- Department
of Biomedicine, University of Bergen, Bergen 5020, Norway
- Computational
Biology Unit, Department of Informatics, University of Bergen, Bergen 5008, Norway
| | - Sneha Dixit
- Department
of Theory and Bio-Systems, Max Planck Institute
of Colloids and Interfaces, Potsdam 14476, Germany
| | - Batuhan Kav
- Institute
of Biological Information Processing: Structural Biochemistry (IBI-7), Forschungszentrum Jülich, Jïulich 52428, Germany
| | - Jesper J. Madsen
- Department
of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, United States
- Center
for Global Health and Infectious Diseases Research, Global and Planetary
Health, College of Public Health, University
of South Florida, Tampa, Florida 33612, United States of America
| | - Markus S. Miettinen
- Department
of Theory and Bio-Systems, Max Planck Institute
of Colloids and Interfaces, Potsdam 14476, Germany
- Computational
Biology Unit, Department of Informatics, University of Bergen, Bergen 5008, Norway
- Department
of Chemistry, University of Bergen, Bergen 5007, Norway
| | - O. H. Samuli Ollila
- VTT Technical
Research Centre of Finland, Espoo 02044, Finland
- Institute
of Biotechnology, University of Helsinki, Helsinki 00014, Finland
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2
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Jensen F. Unifying Charge-Flow Polarization Models. J Chem Theory Comput 2023. [PMID: 37365806 DOI: 10.1021/acs.jctc.3c00341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
We show that several models where electric polarization in molecular systems is modeled by charge-flow between atoms can all be considered as different manifestations of a general underlying mathematical structure. The models can be classified according to whether they employ atomic or bond parameters and whether they employ atom/bond hardness or softness. We show that an ab initio calculated charge response kernel can be considered as the inverse screened Coulombic matrix projected onto the zero-charge subspace, and this may provide a method for deriving charge screening functions to be used in force fields. The analysis suggests that some models contain redundancies, and we argue that a parameterization of charge-flow models in terms of bond softness is preferable as it depends on local quantities and decay to zero upon bond dissociation, while bond hardness depends on global quantities and increases toward infinity upon bond dissociation.
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Affiliation(s)
- Frank Jensen
- Department of Chemistry, Aarhus University, Langelandsgade 140, Aarhus DK-8000, Denmark
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3
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Watkins SL. Current Trends and Changes in Use of Membrane Molecular Dynamics Simulations within Academia and the Pharmaceutical Industry. MEMBRANES 2023; 13:148. [PMID: 36837651 PMCID: PMC9961006 DOI: 10.3390/membranes13020148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/14/2023] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
There has been an almost exponential increase in the use of molecular dynamics simulations in basic research and industry over the last 5 years, with almost a doubling in the number of publications each year. Many of these are focused on neurological membranes, and biological membranes in general, applied to the medical industry. A smaller portion have utilized membrane simulations to answer more basic questions related to the function of specific proteins, chemicals or biological processes. This review covers some newer studies, alongside studies from the last two decades, to determine changes in the field. Some of these are basic, while others are more profound, such as multi-component embedded membrane machinery. It is clear that many facets of the discipline remain the same, while the focus on and uses of the technology are broadening in scope and utilization as a general research tool. Analysis of recent literature provides an overview of the current methodologies, covers some of the recent trends or advances and tries to make predictions of the overall path membrane molecular dynamics will follow in the coming years. In general, the overview presented is geared towards the general scientific community, who may wish to introduce the use of these methodologies in light of these changes, making molecular dynamic simulations more feasible for general scientific or medical research.
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Affiliation(s)
- Stephan L Watkins
- Plant Pathology and CRGB, Oregon State University, 2701 SW Campus Way, Corvallis, OR 97331, USA
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4
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Abstract
We review different models for introducing electric polarization in force fields, with special focus on methods where polarization is modelled at the atomic charge level. While electric polarization has been included in several force fields, the common approach has been to focus on atomic dipole polarizability. Several approaches allow modelling electric polarization by using charge-flow between charge sites instead, but this has been less exploited, despite that atomic charges and charge-flow is expected to be more important than atomic dipoles and dipole polarizability. A number of challenges are required to be solved for charge-flow models to be incorporated into polarizable force fields, for example how to parameterize the models and how to make them computational efficient.
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Affiliation(s)
- Frank Jensen
- Department of Chemistry, Aarhus University, Denmark.
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5
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Hosseini N, Lund M, Ejtehadi MR. Polarization Switching Method for Effective Free Energy Calculation of Membrane Translocation on the Nano-scale. Phys Chem Chem Phys 2022; 24:12281-12292. [DOI: 10.1039/d2cp00056c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Free-energy calculations are crucial for investigating biomolecular interactions on the Nano-scale level. However, in theoretical studies, the neglect of electronic polarization can jeopardize their accuracy and correct predictive capabilities, specifically...
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6
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Mao Y, Loipersberger M, Horn PR, Das A, Demerdash O, Levine DS, Prasad Veccham S, Head-Gordon T, Head-Gordon M. From Intermolecular Interaction Energies and Observable Shifts to Component Contributions and Back Again: A Tale of Variational Energy Decomposition Analysis. Annu Rev Phys Chem 2021; 72:641-666. [PMID: 33636998 DOI: 10.1146/annurev-physchem-090419-115149] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Quantum chemistry in the form of density functional theory (DFT) calculations is a powerful numerical experiment for predicting intermolecular interaction energies. However, no chemical insight is gained in this way beyond predictions of observables. Energy decomposition analysis (EDA) can quantitatively bridge this gap by providing values for the chemical drivers of the interactions, such as permanent electrostatics, Pauli repulsion, dispersion, and charge transfer. These energetic contributions are identified by performing DFT calculations with constraints that disable components of the interaction. This review describes the second-generation version of the absolutely localized molecular orbital EDA (ALMO-EDA-II). The effects of different physical contributions on changes in observables such as structure and vibrational frequencies upon complex formation are characterized via the adiabatic EDA. Example applications include red- versus blue-shifting hydrogen bonds; the bonding and frequency shifts of CO, N2, and BF bound to a [Ru(II)(NH3)5]2 + moiety; and the nature of the strongly bound complexes between pyridine and the benzene and naphthalene radical cations. Additionally, the use of ALMO-EDA-II to benchmark and guide the development of advanced force fields for molecular simulation is illustrated with the recent, very promising, MB-UCB potential.
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Affiliation(s)
- Yuezhi Mao
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Matthias Loipersberger
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Paul R Horn
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Akshaya Das
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA; .,Department of Bioengineering and Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, USA
| | - Omar Demerdash
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA; .,Department of Bioengineering and Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, USA
| | - Daniel S Levine
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Srimukh Prasad Veccham
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
| | - Teresa Head-Gordon
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA; .,Department of Bioengineering and Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, USA
| | - Martin Head-Gordon
- Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, USA;
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7
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Pirillo J, Hijikata Y. Trans Influence across a Metal-Metal Bond of a Paddle-Wheel Unit on Interaction with Gases in a Metal-Organic Framework. Inorg Chem 2020; 59:1193-1203. [PMID: 31825598 DOI: 10.1021/acs.inorgchem.9b02911] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Metal-organic frameworks (MOFs) are known as promising adsorbent materials that can recognize gases specifically. In the frameworks, gases favor interacting with specific binding sites such as open metal sites (OMSs), which can consist of various metals and show characteristic adsorption properties. A recently reported framework possessing OMSs of rhodium paddle-wheel (Rh-PW) showed distinct adsorption properties between NO and CO. We investigated theoretically the reasons for stronger NO binding to the Rh-PW and different adsorption amounts between NO and CO using Rh-PW cluster models, as well as the frequently reported Cu-PW for comparison. We also analyzed the cases of CO2 and N2, which are often used to probe functions of MOFs. We observed an increase in binding energy of NO at the second adduction of NO. On the basis of energy decomposition analysis, we found that Rh-NO bond formation inducing a trans influence is important for the stronger binding than with CO. Furthermore, we proposed a reason for twice the adsorption amount of NO than CO. The results are consistent with experimental observations, giving us insight into design functions of MOFs by selecting metal species.
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Affiliation(s)
- Jenny Pirillo
- Institute for chemical reaction discovery and design (WPI-ICReDD) , Hokkaido University , Kita 21 Nishi 10, Kita-ku , Sapporo , Hokkaido 001-0021 , Japan
| | - Yuh Hijikata
- Institute for chemical reaction discovery and design (WPI-ICReDD) , Hokkaido University , Kita 21 Nishi 10, Kita-ku , Sapporo , Hokkaido 001-0021 , Japan
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8
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Melcr J, Piquemal JP. Accurate Biomolecular Simulations Account for Electronic Polarization. Front Mol Biosci 2019; 6:143. [PMID: 31867342 PMCID: PMC6904368 DOI: 10.3389/fmolb.2019.00143] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/20/2019] [Indexed: 11/29/2022] Open
Abstract
In this perspective, we discuss where and how accounting for electronic many-body polarization affects the accuracy of classical molecular dynamics simulations of biomolecules. While the effects of electronic polarization are highly pronounced for molecules with an opposite total charge, they are also non-negligible for interactions with overall neutral molecules. For instance, neglecting these effects in important biomolecules like amino acids and phospholipids affects the structure of proteins and membranes having a large impact on interpreting experimental data as well as building coarse grained models. With the combined advances in theory, algorithms and computational power it is currently realistic to perform simulations with explicit polarizable dipoles on systems with relevant sizes and complexity. Alternatively, the effects of electronic polarization can also be included at zero additional computational cost compared to standard fixed-charge force fields using the electronic continuum correction, as was recently demonstrated for several classes of biomolecules.
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Affiliation(s)
- Josef Melcr
- Groningen Biomolecular Sciences and Biotechnology Institute and the Zernike Institute for Advanced Materials, University of Groningen, Groningen, Netherlands
| | - Jean-Philip Piquemal
- Laboratoire de Chimie Théorique, Sorbonne Université, UMR7616 CNRS, Paris, France
- Institut Universitaire de France, Paris, France
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, United States
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9
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Pandey P, Aytenfisu AH, MacKerell AD, Mallajosyula SS. Drude Polarizable Force Field Parametrization of Carboxylate and N-Acetyl Amine Carbohydrate Derivatives. J Chem Theory Comput 2019; 15:4982-5000. [PMID: 31411469 PMCID: PMC6852669 DOI: 10.1021/acs.jctc.9b00327] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In this work, we report the development of Drude polarizable force field parameters for the carboxylate and N-acetyl amine derivatives, extending the functionality of the existing Drude polarizable carbohydrate force field. The force field parameters have been developed in a hierarchical manner, reproducing the quantum mechanical gas-phase properties of small model compounds representing the key functional group in the carbohydrate derivatives, including optimization of the electrostatic and bonded parameters. The optimized parameters were then used to generate the models for carboxylate and N-acetyl amine carbohydrate derivatives. The transferred parameters were further tested and optimized to reproduce crystal geometries and J-coupling data from nuclear magnetic resonance experiments. The parameter development resulted in the incorporation of d-glucuronate, l-iduronate, N-acetyl-d-glucosamine (GlcNAc), and N-acetyl-d-galactosamine (GalNAc) sugars into the Drude polarizable force field. The parameters developed in this study were then applied to study the conformational properties of glycosaminoglycan polymer hyaluronan, composed of d-glucuronate and N-acetyl-d-glucosamine, in aqueous solution. Upon comparing the results from the additive and polarizable simulations, it was found that the inclusion of polarization improved the description of the electrostatic interactions observed in hyaluronan, resulting in enhanced conformational flexibility. The developed Drude polarizable force field parameters in conjunction with the remainder of the Drude polarizable force field parameters can be used for future studies involving carbohydrates and their conjugates in complex, heterogeneous systems.
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Affiliation(s)
| | - Asaminew H Aytenfisu
- Department of Pharmaceutical Sciences , University of Maryland School of Pharmacy , 20 Penn Street , Baltimore , Maryland 21201 , United States
| | - Alexander D MacKerell
- Department of Pharmaceutical Sciences , University of Maryland School of Pharmacy , 20 Penn Street , Baltimore , Maryland 21201 , United States
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10
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Marrink SJ, Corradi V, Souza PC, Ingólfsson HI, Tieleman DP, Sansom MS. Computational Modeling of Realistic Cell Membranes. Chem Rev 2019; 119:6184-6226. [PMID: 30623647 PMCID: PMC6509646 DOI: 10.1021/acs.chemrev.8b00460] [Citation(s) in RCA: 419] [Impact Index Per Article: 83.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Indexed: 12/15/2022]
Abstract
Cell membranes contain a large variety of lipid types and are crowded with proteins, endowing them with the plasticity needed to fulfill their key roles in cell functioning. The compositional complexity of cellular membranes gives rise to a heterogeneous lateral organization, which is still poorly understood. Computational models, in particular molecular dynamics simulations and related techniques, have provided important insight into the organizational principles of cell membranes over the past decades. Now, we are witnessing a transition from simulations of simpler membrane models to multicomponent systems, culminating in realistic models of an increasing variety of cell types and organelles. Here, we review the state of the art in the field of realistic membrane simulations and discuss the current limitations and challenges ahead.
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Affiliation(s)
- Siewert J. Marrink
- Groningen
Biomolecular Sciences and Biotechnology Institute & Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Valentina Corradi
- Centre
for Molecular Simulation and Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Paulo C.T. Souza
- Groningen
Biomolecular Sciences and Biotechnology Institute & Zernike Institute
for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Helgi I. Ingólfsson
- Biosciences
and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, United States
| | - D. Peter Tieleman
- Centre
for Molecular Simulation and Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Mark S.P. Sansom
- Department
of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, U.K.
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11
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Abstract
Molecular dynamics (MD) simulations have been widely applied to computer-aided drug design (CADD). While MD has been used in a variety of applications such as free energy perturbation and long-time simulations, the accuracy of the results from those methods depends strongly on the force field used. Force fields for small molecules are crucial, as they not only serve as building blocks for developing force fields for larger biomolecules but also act as model compounds that will be transferred to ligands used in CADD. Currently, a wide range of small molecule force fields based on additive or nonpolarizable models have been developed. While these nonpolarizable force fields can produce reasonable estimations of physical properties and have shown success in a variety of systems, there is still room for improvements due to inherent limitations in these models including the lack of an electronic polarization response. For this reason, incorporating polarization effects into the energy function underlying a force field is believed to be an important step forward, giving rise to the development of polarizable force fields. Recent simulations of biological systems have indicated that polarizable force fields are able to provide a better physical representation of intermolecular interactions and, in many cases, better agreement with experimental properties than nonpolarizable, additive force fields. Therefore, this chapter focuses on the development of small molecule force fields with emphasis on polarizable models. It begins with a brief introduction on the importance of small molecule force fields and their evolution from additive to polarizable force fields. Emphasis is placed on the additive CHARMM General Force Field and the polarizable force field based on the classical Drude oscillator. The theory for the Drude polarizable force field and results for small molecules are presented showing their improvements over the additive model. The potential importance of polarization for their application in a wide range of biological systems including CADD is then discussed.
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Affiliation(s)
- Fang-Yu Lin
- Department of Pharmaceutical Sciences, Computer-Aided Drug Design Center, School of Pharmacy, University of Maryland, Baltimore, MD, USA
| | - Alexander D MacKerell
- Department of Pharmaceutical Sciences, Computer-Aided Drug Design Center, School of Pharmacy, University of Maryland, Baltimore, MD, USA.
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12
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Aytenfisu AH, Yang M, MacKerell AD. CHARMM Drude Polarizable Force Field for Glycosidic Linkages Involving Pyranoses and Furanoses. J Chem Theory Comput 2018; 14:3132-3143. [PMID: 29694037 PMCID: PMC5997548 DOI: 10.1021/acs.jctc.8b00175] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We present an extension of the CHARMM Drude polarizable force field to enable modeling of polysaccharides containing pyranose and furanose monosaccharides. The new force field parameters encompass 1↔2, 1→3, 1→4, and 1→6 pyranose-furanose linkages, 2→1 and 2→6 furanose-furanose linkages, 2→2, 2→3, and 2→4 furanose-pyranose, and 1↔1, 1→2, 1→3, 1→4, and 1→6 pyranose-pyranose linkages. For the glycosidic linkages, both simple model compounds and the full disaccharides with methylation at the reducing end were used for parameter optimization. The model compounds were chosen to be monomers or glycosidic-linked dimers of tetrahydropyran (THP) and tetrahydrofuran (THF). Target data for optimization included one- and two-dimensional potential energy scans of ω and the Φ/Ψ glycosidic dihedral angles in the model compounds and full disaccharides computed by quantum mechanical (QM) RIMP2/cc-pVQZ single point energies on MP2/6-31G(d) optimized structures. Also included in the target data are extensive sets of QM gas phase monohydrate water-saccharide interactions, dipole moments, and molecular polarizabilities for both model compounds and full disaccharides. The resulting polarizable model is shown to be in good agreement with a range of QM data, offering a significant improvement over the additive CHARMM36 carbohydrate force field, as well as experimental data including crystal structures and conformational properties of disaccharides and a trisaccharide in aqueous solution.
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Affiliation(s)
- Asaminew H. Aytenfisu
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, 20 Penn Street, Baltimore, MD 21201, USA
| | - Mingjun Yang
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, 20 Penn Street, Baltimore, MD 21201, USA
- XtalPi Inc., Shennan Road 6025, Futian District, Shenzhen, China
| | - Alexander D. MacKerell
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, 20 Penn Street, Baltimore, MD 21201, USA
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13
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Sedghamiz E, Ghalami F. Evaluating the Effects of Geometry and Charge Flux in Force Field Modeling. J Phys Chem A 2018; 122:4647-4653. [PMID: 29698601 DOI: 10.1021/acs.jpca.7b12198] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We apply a model for analyzing the importance of conformational charge flux to 11 molecules with the R-(CH2) n-R structure (R = Cl, F, OH, SH, COOH, CONH2, and NH2 and n = 4-6). Atomic charges were obtained by fitting to results from density functional theory calculations using the HLY procedure, and their geometry dependence is decomposed into contributions from changes in bond lengths, bond angles, and torsional angles. The torsional degrees of freedom are the main contribution to the conformational dependence of atomic charges and molecular dipole moments, but indirect effects due to changes in bond distances and angles account for ∼15% of the variations. While the magnitude of charge flux and geometry effects have been found to be independent of the number of internal degrees of freedom, the nature of the R- group has a moderate influence. The indirect effects are comparable for all of the R-groups and are approximately one-half the magnitude of the corresponding effects in peptide models. However, the magnitudes are different, yet the relative importance of geometry and charge flux effects are completely similar to those of the peptide models, which suggests that modeling the charge flux effects for changes in bond lengths, bond angles, and torsional angles should be considered for developing improved force fields.
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Affiliation(s)
- Elaheh Sedghamiz
- Department of Chemistry , Aarhus University , Langelandsgade 140 , Aarhus DK-8000 , Denmark.,Department of Chemistry , University of Isfahan , Isfahan 81746-73441 , Iran
| | - Farhad Ghalami
- Department of Chemistry , Aarhus University , Langelandsgade 140 , Aarhus DK-8000 , Denmark.,Department of Chemistry , University of Isfahan , Isfahan 81746-73441 , Iran
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14
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Melcr J, Martinez-Seara H, Nencini R, Kolafa J, Jungwirth P, Ollila OHS. Accurate Binding of Sodium and Calcium to a POPC Bilayer by Effective Inclusion of Electronic Polarization. J Phys Chem B 2018; 122:4546-4557. [DOI: 10.1021/acs.jpcb.7b12510] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Josef Melcr
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 117 20 Prague 6, Czech Republic
| | - Hector Martinez-Seara
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 117 20 Prague 6, Czech Republic
| | - Ricky Nencini
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 117 20 Prague 6, Czech Republic
| | - Jiří Kolafa
- Department of Physical Chemistry, Institute of Chemical Technology, 166 28 Prague 6, Czech Republic
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 117 20 Prague 6, Czech Republic
- Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - O. H. Samuli Ollila
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 117 20 Prague 6, Czech Republic
- Institute of Biotechnology, University of Helsinki, 00100 Helsinki, Finland
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15
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Li H, Chowdhary J, Huang L, He X, MacKerell AD, Roux B. Drude Polarizable Force Field for Molecular Dynamics Simulations of Saturated and Unsaturated Zwitterionic Lipids. J Chem Theory Comput 2017; 13:4535-4552. [PMID: 28731702 DOI: 10.1021/acs.jctc.7b00262] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Additive force fields are designed to account for induced electronic polarization in a mean-field average way, using effective empirical fixed charges. The limitation of this approximation is cause for serious concerns, particularly in the case of lipid membranes, where the molecular environment undergoes dramatic variations over microscopic length scales. A polarizable force field based on the classical Drude oscillator offers a practical and computationally efficient framework for an improved representation of electrostatic interactions in molecular simulations. Building on the first-generation Drude polarizable force field for the dipalmitoylphosphatidylcholine 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) molecule, the present effort was undertaken to improve this initial model and expand the force field to a wider range of phospholipid molecules. New lipids parametrized include dimyristoylphosphatidylcholine (DMPC), dilauroylphosphatidylcholine (DLPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), dipalmitoylphosphatidylethanolamine (DPPE), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE), and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE). The iterative optimization protocol employed in this effort led to lipid models that achieve a good balance between reproducing quantum mechanical data on model compound representative of phospholipids and reproducing a range of experimental condensed phase properties of bilayers. A parametrization strategy based on a restrained ensemble-maximum entropy methodology was used to help accurately match the experimental NMR order parameters in the polar headgroup region. All the parameters were developed to be compatible with the remainder of the Drude polarizable force field, which includes water, ions, proteins, DNA, and selected carbohydrates.
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Affiliation(s)
- Hui Li
- Department of Biochemistry and Molecular Biology, Gordon Center for Integrative Science, University of Chicago , Chicago, Illinois 60637, United States
| | - Janamejaya Chowdhary
- Department of Biochemistry and Molecular Biology, Gordon Center for Integrative Science, University of Chicago , Chicago, Illinois 60637, United States
| | - Lei Huang
- Department of Biochemistry and Molecular Biology, Gordon Center for Integrative Science, University of Chicago , Chicago, Illinois 60637, United States
| | - Xibing He
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore , Baltimore, Maryland 21201, United States
| | - Alexander D MacKerell
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore , Baltimore, Maryland 21201, United States
| | - Benoît Roux
- Department of Biochemistry and Molecular Biology, Gordon Center for Integrative Science, University of Chicago , Chicago, Illinois 60637, United States
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16
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Naserifar S, Brooks DJ, Goddard WA, Cvicek V. Polarizable charge equilibration model for predicting accurate electrostatic interactions in molecules and solids. J Chem Phys 2017; 146:124117. [DOI: 10.1063/1.4978891] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Affiliation(s)
- Saber Naserifar
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, USA
| | - Daniel J. Brooks
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, USA
| | - William A. Goddard
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, USA
| | - Vaclav Cvicek
- Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, USA
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17
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Lemkul J, Huang J, Roux B, MacKerell AD. An Empirical Polarizable Force Field Based on the Classical Drude Oscillator Model: Development History and Recent Applications. Chem Rev 2016; 116:4983-5013. [PMID: 26815602 PMCID: PMC4865892 DOI: 10.1021/acs.chemrev.5b00505] [Citation(s) in RCA: 376] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Indexed: 11/28/2022]
Abstract
Molecular mechanics force fields that explicitly account for induced polarization represent the next generation of physical models for molecular dynamics simulations. Several methods exist for modeling induced polarization, and here we review the classical Drude oscillator model, in which electronic degrees of freedom are modeled by charged particles attached to the nuclei of their core atoms by harmonic springs. We describe the latest developments in Drude force field parametrization and application, primarily in the last 15 years. Emphasis is placed on the Drude-2013 polarizable force field for proteins, DNA, lipids, and carbohydrates. We discuss its parametrization protocol, development history, and recent simulations of biologically interesting systems, highlighting specific studies in which induced polarization plays a critical role in reproducing experimental observables and understanding physical behavior. As the Drude oscillator model is computationally tractable and available in a wide range of simulation packages, it is anticipated that use of these more complex physical models will lead to new and important discoveries of the physical forces driving a range of chemical and biological phenomena.
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Affiliation(s)
- Justin
A. Lemkul
- Department
of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Baltimore, Maryland 21201, United States
| | - Jing Huang
- Department
of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Baltimore, Maryland 21201, United States
| | - Benoît Roux
- Department
of Biochemistry and Molecular Biology, University
of Chicago, Chicago, Illinois 60637, United
States
| | - Alexander D. MacKerell
- Department
of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Baltimore, Maryland 21201, United States
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18
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19
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Baoukina S, Tieleman DP. Computer simulations of lung surfactant. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:2431-2440. [PMID: 26922885 DOI: 10.1016/j.bbamem.2016.02.030] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 02/21/2016] [Accepted: 02/23/2016] [Indexed: 01/26/2023]
Abstract
Lung surfactant lines the gas-exchange interface in the lungs and reduces the surface tension, which is necessary for breathing. Lung surfactant consists mainly of lipids with a small amount of proteins and forms a monolayer at the air-water interface connected to bilayer reservoirs. Lung surfactant function involves transfer of material between the monolayer and bilayers during the breathing cycle. Lipids and proteins are organized laterally in the monolayer; selected species are possibly preferentially transferred to bilayers. The complex 3D structure of lung surfactant and the exact roles of lipid organization and proteins remain important goals for research. We review recent simulation studies on the properties of lipid monolayers, monolayers with phase coexistence, monolayer-bilayer transformations, lipid-protein interactions, and effects of nanoparticles on lung surfactant. This article is part of a Special Issue entitled: Biosimulations edited by Ilpo Vattulainen and Tomasz Róg.
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Affiliation(s)
- Svetlana Baoukina
- Department of Biological Sciences and Centre for Molecular Simulation, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada.
| | - D Peter Tieleman
- Department of Biological Sciences and Centre for Molecular Simulation, University of Calgary, 2500 University Dr. NW, Calgary, AB T2N 1N4, Canada.
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20
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Szklarczyk OM, Arvaniti E, van Gunsteren WF. Polarizable coarse-grained models for molecular dynamics simulation of liquid cyclohexane. J Comput Chem 2015; 36:1311-21. [DOI: 10.1002/jcc.23929] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 03/09/2015] [Accepted: 03/12/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Oliwia M. Szklarczyk
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences; Swiss Federal Institute of Technology ETH; 8093 Zürich Switzerland
| | - Eirini Arvaniti
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences; Swiss Federal Institute of Technology ETH; 8093 Zürich Switzerland
| | - Wilfred F. van Gunsteren
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences; Swiss Federal Institute of Technology ETH; 8093 Zürich Switzerland
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21
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Baker CM. Polarizable force fields for molecular dynamics simulations of biomolecules. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2015. [DOI: 10.1002/wcms.1215] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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22
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Skelton AA, Agrawal N, Fried JR. Quantum mechanical calculations of the interactions between diazacrowns and the sodium cation: an insight into Na+ complexation in diazacrown-based synthetic ion channels. RSC Adv 2015. [DOI: 10.1039/c4ra14000a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Quantum mechanical calculations were performed to study the conformational behavior and complexation between a sodium cation and a diazacrown (diaza-18-crown-6) using density functional theory (DFT), Møller–Plesset (MP2) and molecular mechanics methods.
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Affiliation(s)
- A. A. Skelton
- School of Health Sciences
- Discipline of Pharmacy
- University of KwaZulu-Natal
- South Africa
| | - N. Agrawal
- School of Health Sciences
- Discipline of Pharmacy
- University of KwaZulu-Natal
- South Africa
| | - J. R. Fried
- Chemical Engineering
- University of Louisville
- Louisville, USA
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23
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Huang J, Lopes PM, Roux B, MacKerell AD. Recent Advances in Polarizable Force Fields for Macromolecules: Microsecond Simulations of Proteins Using the Classical Drude Oscillator Model. J Phys Chem Lett 2014; 5:3144-3150. [PMID: 25247054 PMCID: PMC4167036 DOI: 10.1021/jz501315h] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 08/27/2014] [Indexed: 05/13/2023]
Abstract
In this Perspective, we summarize recent efforts to include the explicit treatment of induced electronic polarization in biomolecular force fields. Methods used to treat polarizability, including the induced dipole, fluctuating charge, and classical Drude oscillator models, are presented, including recent advances in force fields using those methods. This is followed by recent results obtained with the Drude model, including microsecond molecular dynamics (MD) simulations of multiple proteins in explicit solvent. Results show significant variability of backbone and side-chain dipole moments as a function of environment, including significant changes during individual simulations. Dipole moments of water in the vicinity of the proteins reveal small but systematic changes, with the direction of the changes dependent on the environment. Analyses of the full proteins show that the polarizable Drude model leads to larger values of the dielectric constant of the protein interior, especially in the case of hydrophobic regions. These results indicate that the inclusion of explicit electronic polarizability leads to significant differences in the physical forces affecting the structure and dynamics of proteins, which can be investigated in a computationally tractable fashion in the context of the Drude model.
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Affiliation(s)
- Jing Huang
- Department
of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, Room 629, Baltimore, Maryland 21201, United States
| | - Pedro
E. M. Lopes
- Department
of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, Room 629, Baltimore, Maryland 21201, United States
| | - Benoît Roux
- Department
of Biochemistry and Molecular Biology, University
of Chicago, Chicago, Illinois 60637, United
States
| | - Alexander D. MacKerell
- Department
of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, Room 629, Baltimore, Maryland 21201, United States
- E-mail: . Phone: (410) 706-7442. Fax: (410) 706-5017
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24
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Maciejewski A, Pasenkiewicz-Gierula M, Cramariuc O, Vattulainen I, Rog T. Refined OPLS all-atom force field for saturated phosphatidylcholine bilayers at full hydration. J Phys Chem B 2014; 118:4571-81. [PMID: 24745688 DOI: 10.1021/jp5016627] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report parametrization of dipalmitoyl-phosphatidylcholine (DPPC) in the framework of the Optimized Parameters for Liquid Simulations all-atom (OPLS-AA) force field. We chose DPPC as it is one of the most studied phospholipid species and thus has plenty of experimental data necessary for model validation, and it is also one of the highly important and abundant lipid types, e.g., in lung surfactant. Overall, PCs have not been previously parametrized in the OPLS-AA force field; thus, there is a need to derive its bonding and nonbonding parameters for both the polar and nonpolar parts of the molecule. In the present study, we determined the parameters for torsion angles in the phosphatidylcholine and glycerol moieties and in the acyl chains, as well the partial atomic charges. In these calculations, we used three methods: (1) Hartree-Fock (HF), (2) second order Møller-Plesset perturbation theory (MP2), and (3) density functional theory (DFT). We also tested the effect of the polar environment by using the polarizable continuum model (PCM), and for acyl chains the van der Waals parameters were also adjusted. In effect, six parameter sets were generated and tested on a DPPC bilayer. Out of these six sets, only one was found to be able to satisfactorily reproduce experimental data for the lipid bilayer. The successful DPPC model was obtained from MP2 calculations in an implicit polar environment (PCM).
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Affiliation(s)
- Arkadiusz Maciejewski
- Department of Physics, Tampere University of Technology , PO Box 692, FI-33101 Tampere, Finland
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25
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He X, Lopes PEM, MacKerell AD. Polarizable empirical force field for acyclic polyalcohols based on the classical Drude oscillator. Biopolymers 2013; 99:724-38. [PMID: 23703219 PMCID: PMC3902549 DOI: 10.1002/bip.22286] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 05/05/2013] [Indexed: 01/12/2023]
Abstract
A polarizable empirical force field for acyclic polyalcohols based on the classical Drude oscillator is presented. The model is optimized with an emphasis on the transferability of the developed parameters among molecules of different sizes in this series and on the condensed-phase properties validated against experimental data. The importance of the explicit treatment of electronic polarizability in empirical force fields is demonstrated in the cases of this series of molecules with vicinal hydroxyl groups that can form cooperative intra- and intermolecular hydrogen bonds. Compared to the CHARMM additive force field, improved treatment of the electrostatic interactions avoids overestimation of the gas-phase dipole moments resulting in significant improvement in the treatment of the conformational energies and leads to the correct balance of intra- and intermolecular hydrogen bonding of glycerol as evidenced by calculated heat of vaporization being in excellent agreement with experiment. Computed condensed phase data, including crystal lattice parameters and volumes and densities of aqueous solutions are in better agreement with experimental data as compared to the corresponding additive model. Such improvements are anticipated to significantly improve the treatment of polymers in general, including biological macromolecules.
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Affiliation(s)
- Xibing He
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, Baltimore, MD 21201
| | - Pedro E. M. Lopes
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, Baltimore, MD 21201
| | - Alexander D. MacKerell
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, Baltimore, MD 21201
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26
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Baker CM, Best RB. Insights into the Binding of Intrinsically Disordered Proteins from Molecular Dynamics Simulation. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2013; 4:182-198. [PMID: 34354764 DOI: 10.1002/wcms.1167] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Intrinsically disordered proteins (IDPs) are a class of protein that, in the native state, possess no well-defined secondary or tertiary structure, existing instead as dynamic ensembles of conformations. They are biologically important, with approximately 20% of all eukaryotic proteins disordered, and found at the heart of many biochemical networks. To fulfil their biological roles, many IDPs need to bind to proteins and/or nucleic acids. And while unstructured in solution, IDPs typically fold into a well-defined three-dimensional structure upon interaction with a binding partner. The flexibility and structural diversity inherent to IDPs makes this coupled folding and binding difficult to study at atomic resolution by experiment alone, and computer simulation currently offers perhaps the best opportunity to understand this process. But simulation of coupled folding and binding is itself extremely challenging; these molecules are large and highly flexible, and their binding partners, such as DNA or cyclins, are also often large. Therefore, their study requires either or both simplified representations and advanced enhanced sampling schemes. It is not always clear that existing simulation techniques, optimized for studying folded proteins, are well-suited to IDPs. In this article, we examine the progress that has been made in the study of coupled folding and binding using molecular dynamics simulation. We summarise what has been learnt, and examine the state of the art in terms of both methodologies and models. We also consider the lessons to be learnt from advances in other areas of simulation and highlight the issues that remain of be addressed.
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Affiliation(s)
- Christopher M Baker
- University of Cambridge, Department of Chemistry, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Robert B Best
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, USA
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27
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Janosi L, Ceccarelli M. The gating mechanism of the human aquaporin 5 revealed by molecular dynamics simulations. PLoS One 2013; 8:e59897. [PMID: 23565173 PMCID: PMC3614956 DOI: 10.1371/journal.pone.0059897] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 02/19/2013] [Indexed: 11/29/2022] Open
Abstract
Aquaporins are protein channels located across the cell membrane with the role of conducting water or other small sugar alcohol molecules (aquaglyceroporins). The high-resolution X-ray structure of the human aquaporin 5 (HsAQP5) shows that HsAQP5, as all the other known aquaporins, exhibits tetrameric structure. By means of molecular dynamics simulations we analyzed the role of spontaneous fluctuations on the structural behavior of the human AQP5. We found that different conformations within the tetramer lead to a distribution of monomeric channel structures, which can be characterized as open or closed. The switch between the two states of a channel is a tap-like mechanism at the cytoplasmic end which regulates the water passage through the pore. The channel is closed by a translation of the His67 residue inside the pore. Moreover, water permeation rate calculations revealed that the selectivity filter, located at the other end of the channel, regulates the flow rate of water molecules when the channel is open, by locally modifying the orientation of His173. Furthermore, the calculated permeation rates of a fully open channel are in good agreement with the reported experimental value.
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Affiliation(s)
- Lorant Janosi
- Department of Physics, University of Cagliari, Cagliari, Italy.
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28
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Yao XX, Ji CG, Xie DQ, Zhang JZ. Molecular dynamics study of DNA binding by INT-DBD under a polarized force field. J Comput Chem 2013; 34:1136-42. [DOI: 10.1002/jcc.23244] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 11/08/2012] [Accepted: 12/30/2012] [Indexed: 11/06/2022]
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