1
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Kalayan J, Ramzan I, Williams CD, Bryce RA, Burton NA. A neural network potential based on pairwise resolved atomic forces and energies. J Comput Chem 2024; 45:1143-1151. [PMID: 38284556 DOI: 10.1002/jcc.27313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/23/2023] [Accepted: 01/05/2024] [Indexed: 01/30/2024]
Abstract
Molecular simulations have become a key tool in molecular and materials design. Machine learning (ML)-based potential energy functions offer the prospect of simulating complex molecular systems efficiently at quantum chemical accuracy. In previous work, we have introduced the ML-based PairF-Net approach to neural network potentials, that adopts a pairwise interatomic scheme to predicting forces within a molecular system. Here, we further develop the PairF-Net model to intrinsically incorporate energy conservation and couple the model to a molecular mechanical (MM) environment within the OpenMM package. The updated PairF-Net model yields energy and force predictions and dynamical distributions in good agreement with the rMD17 dataset of ten small organic molecules in the gas-phase. We further show that these in vacuo ML models of small molecules can be applied to force predictions in aqueous solution via hybrid ML/MM simulations. We present a new benchmark dataset for these ten molecules in solution, obtained from QM/MM simulations, which we denote as rMD17-aq (https://zenodo.org/records/10048644); and assess the ability of PairF-Net to reproduce the molecular energy, atomic forces and dynamical distributions of these solution conformations via ML/MM simulations.
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Affiliation(s)
- Jas Kalayan
- Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
| | - Ismaeel Ramzan
- Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
- Neural Circuits and Computations Unit, RIKEN Center for Brain Science, Wako, Japan
| | - Christopher D Williams
- Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
| | - Richard A Bryce
- Division of Pharmacy and Optometry, School of Health Sciences, University of Manchester, Manchester, UK
| | - Neil A Burton
- Department of Chemistry, University of Manchester, Manchester, UK
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2
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Tzeliou CE, Mermigki MA, Tzeli D. Review on the QM/MM Methodologies and Their Application to Metalloproteins. Molecules 2022; 27:molecules27092660. [PMID: 35566011 PMCID: PMC9105939 DOI: 10.3390/molecules27092660] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/12/2022] [Accepted: 04/18/2022] [Indexed: 12/04/2022] Open
Abstract
The multiscaling quantum mechanics/molecular mechanics (QM/MM) approach was introduced in 1976, while the extensive acceptance of this methodology started in the 1990s. The combination of QM/MM approach with molecular dynamics (MD) simulation, otherwise known as the QM/MM/MD approach, is a powerful and promising tool for the investigation of chemical reactions’ mechanism of complex molecular systems, drug delivery, properties of molecular devices, organic electronics, etc. In the present review, the main methodologies in the multiscaling approaches, i.e., density functional theory (DFT), semiempirical methodologies (SE), MD simulations, MM, and their new advances are discussed in short. Then, a review on calculations and reactions on metalloproteins is presented, where particular attention is given to nitrogenase that catalyzes the conversion of atmospheric nitrogen molecules N₂ into NH₃ through the process known as nitrogen fixation and the FeMo-cofactor.
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Affiliation(s)
- Christina Eleftheria Tzeliou
- Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 157 71 Athens, Greece; (C.E.T.); (M.A.M.)
| | - Markella Aliki Mermigki
- Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 157 71 Athens, Greece; (C.E.T.); (M.A.M.)
| | - Demeter Tzeli
- Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 157 71 Athens, Greece; (C.E.T.); (M.A.M.)
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., 116 35 Athens, Greece
- Correspondence: ; Tel.: +30-210-727-4307
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3
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Abstract
QM/MM simulations have become an indispensable tool in many chemical and biochemical investigations. Considering the tremendous degree of success, including recognition by a 2013 Nobel Prize in Chemistry, are there still "burning challenges" in QM/MM methods, especially for biomolecular systems? In this short Perspective, we discuss several issues that we believe greatly impact the robustness and quantitative applicability of QM/MM simulations to many, if not all, biomolecules. We highlight these issues with observations and relevant advances from recent studies in our group and others in the field. Despite such limited scope, we hope the discussions are of general interest and will stimulate additional developments that help push the field forward in meaningful directions.
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Affiliation(s)
- Qiang Cui
- Departments of Chemistry, Physics, and Biomedical Engineering, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Tanmoy Pal
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Luke Xie
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
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4
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Mühlbach AH, Reiher M. Quantum system partitioning at the single-particle level. J Chem Phys 2018; 149:184104. [DOI: 10.1063/1.5055942] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Adrian H. Mühlbach
- Laboratorium für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Markus Reiher
- Laboratorium für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
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5
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Christensen AS, Kromann JC, Jensen JH, Cui Q. Intermolecular interactions in the condensed phase: Evaluation of semi-empirical quantum mechanical methods. J Chem Phys 2018; 147:161704. [PMID: 29096452 DOI: 10.1063/1.4985605] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
To facilitate further development of approximate quantum mechanical methods for condensed phase applications, we present a new benchmark dataset of intermolecular interaction energies in the solution phase for a set of 15 dimers, each containing one charged monomer. The reference interaction energy in solution is computed via a thermodynamic cycle that integrates dimer binding energy in the gas phase at the coupled cluster level and solute-solvent interaction with density functional theory; the estimated uncertainty of such calculated interaction energy is ±1.5 kcal/mol. The dataset is used to benchmark the performance of a set of semi-empirical quantum mechanical (SQM) methods that include DFTB3-D3, DFTB3/CPE-D3, OM2-D3, PM6-D3, PM6-D3H+, and PM7 as well as the HF-3c method. We find that while all tested SQM methods tend to underestimate binding energies in the gas phase with a root-mean-squared error (RMSE) of 2-5 kcal/mol, they overestimate binding energies in the solution phase with an RMSE of 3-4 kcal/mol, with the exception of DFTB3/CPE-D3 and OM2-D3, for which the systematic deviation is less pronounced. In addition, we find that HF-3c systematically overestimates binding energies in both gas and solution phases. As most approximate QM methods are parametrized and evaluated using data measured or calculated in the gas phase, the dataset represents an important first step toward calibrating QM based methods for application in the condensed phase where polarization and exchange repulsion need to be treated in a balanced fashion.
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Affiliation(s)
- Anders S Christensen
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
| | - Jimmy C Kromann
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Jan H Jensen
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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6
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Cui Q. Perspective: Quantum mechanical methods in biochemistry and biophysics. J Chem Phys 2017; 145:140901. [PMID: 27782516 DOI: 10.1063/1.4964410] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In this perspective article, I discuss several research topics relevant to quantum mechanical (QM) methods in biophysical and biochemical applications. Due to the immense complexity of biological problems, the key is to develop methods that are able to strike the proper balance of computational efficiency and accuracy for the problem of interest. Therefore, in addition to the development of novel ab initio and density functional theory based QM methods for the study of reactive events that involve complex motifs such as transition metal clusters in metalloenzymes, it is equally important to develop inexpensive QM methods and advanced classical or quantal force fields to describe different physicochemical properties of biomolecules and their behaviors in complex environments. Maintaining a solid connection of these more approximate methods with rigorous QM methods is essential to their transferability and robustness. Comparison to diverse experimental observables helps validate computational models and mechanistic hypotheses as well as driving further development of computational methodologies.
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Affiliation(s)
- Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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7
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Tuna D, Lu Y, Koslowski A, Thiel W. Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Benchmarks of Electronically Excited States. J Chem Theory Comput 2016; 12:4400-22. [DOI: 10.1021/acs.jctc.6b00403] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Deniz Tuna
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
| | - You Lu
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
| | - Axel Koslowski
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany
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8
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Christensen A, Kubař T, Cui Q, Elstner M. Semiempirical Quantum Mechanical Methods for Noncovalent Interactions for Chemical and Biochemical Applications. Chem Rev 2016; 116:5301-37. [PMID: 27074247 PMCID: PMC4867870 DOI: 10.1021/acs.chemrev.5b00584] [Citation(s) in RCA: 246] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Indexed: 12/28/2022]
Abstract
Semiempirical (SE) methods can be derived from either Hartree-Fock or density functional theory by applying systematic approximations, leading to efficient computational schemes that are several orders of magnitude faster than ab initio calculations. Such numerical efficiency, in combination with modern computational facilities and linear scaling algorithms, allows application of SE methods to very large molecular systems with extensive conformational sampling. To reliably model the structure, dynamics, and reactivity of biological and other soft matter systems, however, good accuracy for the description of noncovalent interactions is required. In this review, we analyze popular SE approaches in terms of their ability to model noncovalent interactions, especially in the context of describing biomolecules, water solution, and organic materials. We discuss the most significant errors and proposed correction schemes, and we review their performance using standard test sets of molecular systems for quantum chemical methods and several recent applications. The general goal is to highlight both the value and limitations of SE methods and stimulate further developments that allow them to effectively complement ab initio methods in the analysis of complex molecular systems.
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Affiliation(s)
- Anders
S. Christensen
- Department
of Chemistry and Theoretical Chemistry Institute, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Tomáš Kubař
- Institute of Physical
Chemistry & Center for Functional Nanostructures and Institute of Physical
Chemistry, Karlsruhe Institute of Technology, Kaiserstrasse 12, 76131 Karlsruhe, Germany
| | - Qiang Cui
- Department
of Chemistry and Theoretical Chemistry Institute, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Marcus Elstner
- Institute of Physical
Chemistry & Center for Functional Nanostructures and Institute of Physical
Chemistry, Karlsruhe Institute of Technology, Kaiserstrasse 12, 76131 Karlsruhe, Germany
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9
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Dral P, Wu X, Spörkel L, Koslowski A, Thiel W. Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Benchmarks for Ground-State Properties. J Chem Theory Comput 2016; 12:1097-120. [PMID: 26771261 PMCID: PMC4785506 DOI: 10.1021/acs.jctc.5b01047] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Indexed: 11/30/2022]
Abstract
The semiempirical orthogonalization-corrected OMx methods (OM1, OM2, and OM3) go beyond the standard MNDO model by including additional interactions in the electronic structure calculation. When augmented with empirical dispersion corrections, the resulting OMx-Dn approaches offer a fast and robust treatment of noncovalent interactions. Here we evaluate the performance of the OMx and OMx-Dn methods for a variety of ground-state properties using a large and diverse collection of benchmark sets from the literature, with a total of 13035 original and derived reference data. Extensive comparisons are made with the results from established semiempirical methods (MNDO, AM1, PM3, PM6, and PM7) that also use the NDDO (neglect of diatomic differential overlap) integral approximation. Statistical evaluations show that the OMx and OMx-Dn methods outperform the other methods for most of the benchmark sets.
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Affiliation(s)
- Pavlo
O. Dral
- Max-Planck-Institut für
Kohlenforschung, Kaiser-Wilhelm-Platz
1, 45470 Mülheim
an der Ruhr, Germany
| | - Xin Wu
- Max-Planck-Institut für
Kohlenforschung, Kaiser-Wilhelm-Platz
1, 45470 Mülheim
an der Ruhr, Germany
| | - Lasse Spörkel
- Max-Planck-Institut für
Kohlenforschung, Kaiser-Wilhelm-Platz
1, 45470 Mülheim
an der Ruhr, Germany
| | - Axel Koslowski
- Max-Planck-Institut für
Kohlenforschung, Kaiser-Wilhelm-Platz
1, 45470 Mülheim
an der Ruhr, Germany
| | - Walter Thiel
- Max-Planck-Institut für
Kohlenforschung, Kaiser-Wilhelm-Platz
1, 45470 Mülheim
an der Ruhr, Germany
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10
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Dral PO, Wu X, Spörkel L, Koslowski A, Weber W, Steiger R, Scholten M, Thiel W. Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Theory, Implementation, and Parameters. J Chem Theory Comput 2016; 12:1082-96. [PMID: 26771204 PMCID: PMC4785507 DOI: 10.1021/acs.jctc.5b01046] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Semiempirical orthogonalization-corrected
methods (OM1, OM2, and
OM3) go beyond the standard MNDO model by explicitly including additional
interactions into the Fock matrix in an approximate manner (Pauli
repulsion, penetration effects, and core–valence interactions),
which yields systematic improvements both for ground-state and excited-state
properties. In this Article, we describe the underlying theoretical
formalism of the OMx methods and their implementation
in full detail, and we report all relevant OMx parameters
for hydrogen, carbon, nitrogen, oxygen, and fluorine. For a standard
set of mostly organic molecules commonly used in semiempirical method
development, the OMx results are found to be superior
to those from standard MNDO-type methods. Parametrized Grimme-type
dispersion corrections can be added to OM2 and OM3 energies to provide
a realistic treatment of noncovalent interaction energies, as demonstrated
for the complexes in the S22 and S66×8 test sets.
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Affiliation(s)
- Pavlo O Dral
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Xin Wu
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Lasse Spörkel
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Axel Koslowski
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Wolfgang Weber
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Rainer Steiger
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Mirjam Scholten
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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11
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El-Kareem MSMA, Rabbih MAEF, Selim ETM, Elsherbiny EAEM, El-Khateeb AY. Application of GC/EIMS in Combination with Semi-Empirical Calculations for Identification and Investigation of Some Volatile Components in Basil Essential Oil. INTERNATIONAL JOURNAL OF ANALYTICAL MASS SPECTROMETRY AND CHROMATOGRAPHY 2016; 04:14-25. [DOI: 10.4236/ijamsc.2016.41002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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12
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Gaus M, Jin H, Demapan D, Christensen AS, Goyal P, Elstner M, Cui Q. DFTB3 Parametrization for Copper: The Importance of Orbital Angular Momentum Dependence of Hubbard Parameters. J Chem Theory Comput 2015; 11:4205-19. [PMID: 26575916 PMCID: PMC4827604 DOI: 10.1021/acs.jctc.5b00600] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the parametrization of a density functional tight binding method (DFTB3) for copper in a spin-polarized formulation. The parametrization is consistent with the framework of 3OB for main group elements (ONCHPS) and can be readily used for biological applications that involve copper proteins/peptides. The key to our parametrization is to introduce orbital angular momentum dependence of the Hubbard parameter and its charge derivative, thus allowing the 3d and 4s orbitals to adopt different sizes and responses to the change of charge state. The parametrization has been tested by applying to a fairly broad set of molecules of biological relevance, and the properties of interest include optimized geometries, ligand binding energies, and ligand proton affinities. Compared to the reference QM level (B3LYP/aug-cc-pVTZ, which is shown here to be similar to the B97-1 and CCSD(T) results, in terms of many properties of interest for a set of small copper containing molecules), our parametrization generally gives reliable structural properties for both Cu(I) and Cu(II) compounds, although several exceptions are also noted. For energetics, the results are more accurate for neutral ligands than for charged ligands, likely reflecting the minimal basis limitation of DFTB3; the results generally outperform NDDO based methods such as PM6 and even PBE with the 6-31+G(d,p) basis. For all ligand types, single-point B3LYP calculations at DFTB3 geometries give results very close (∼1-2 kcal/mol) to the reference B3LYP values, highlighting the consistency between DFTB3 and B3LYP structures. Possible further developments of the DFTB3 model for a better treatment of transition-metal ions are also discussed. In the current form, our first generation of DFTB3 copper model is expected to be particularly valuable as a method that drives sampling in systems that feature a dynamical copper binding site.
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Affiliation(s)
- Michael Gaus
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Haiyun Jin
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Darren Demapan
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Anders S Christensen
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Puja Goyal
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Marcus Elstner
- Institute of Physical Chemistry, Karlsruhe Institute of Technology , Kaiserstr. 12, 76131 Karlsruhe, Germany
| | - Qiang Cui
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
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13
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Nikiforov A, Gamez JA, Thiel W, Huix-Rotllant M, Filatov M. Assessment of approximate computational methods for conical intersections and branching plane vectors in organic molecules. J Chem Phys 2015; 141:124122. [PMID: 25273427 DOI: 10.1063/1.4896372] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Quantum-chemical computational methods are benchmarked for their ability to describe conical intersections in a series of organic molecules and models of biological chromophores. Reference results for the geometries, relative energies, and branching planes of conical intersections are obtained using ab initio multireference configuration interaction with single and double excitations (MRCISD). They are compared with the results from more approximate methods, namely, the state-interaction state-averaged restricted ensemble-referenced Kohn-Sham method, spin-flip time-dependent density functional theory, and a semiempirical MRCISD approach using an orthogonalization-corrected model. It is demonstrated that these approximate methods reproduce the ab initio reference data very well, with root-mean-square deviations in the optimized geometries of the order of 0.1 Å or less and with reasonable agreement in the computed relative energies. A detailed analysis of the branching plane vectors shows that all currently applied methods yield similar nuclear displacements for escaping the strong non-adiabatic coupling region near the conical intersections. Our comparisons support the use of the tested quantum-chemical methods for modeling the photochemistry of large organic and biological systems.
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Affiliation(s)
- Alexander Nikiforov
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Jose A Gamez
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Miquel Huix-Rotllant
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany
| | - Michael Filatov
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Universität Bonn, Beringstr. 4, D-53115 Bonn, Germany
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14
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Thiel W. Semiempirical quantum–chemical methods. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2013. [DOI: 10.1002/wcms.1161] [Citation(s) in RCA: 171] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Walter Thiel
- Max‐Planck‐Institut für KohlenforschungMülheimGermany
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15
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Gaus M, Cui Q, Elstner M. Density functional tight binding: application to organic and biological molecules. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2013. [DOI: 10.1002/wcms.1156] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Michael Gaus
- Department of Chemistry and Theoretical Chemistry Institute University of Wisconsin Madison WI 53706 USA
| | - Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute University of Wisconsin Madison WI 53706 USA
| | - Marcus Elstner
- Karlsruhe Institute of Technology Physical Chemistry, Kaiserstrasse 12 D‐76131 Karlsruhe Germany
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16
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Pang X, Han K, Cui Q. A simple but effective modeling strategy for structural properties of non-heme Fe(II) sites in proteins: test of force field models and application to proteins in the AlkB family. J Comput Chem 2013; 34:1620-35. [PMID: 23666816 DOI: 10.1002/jcc.23305] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 03/09/2013] [Accepted: 04/03/2013] [Indexed: 12/25/2022]
Abstract
To facilitate computational study of proteins in the AlkB family and related α-ketoglutarate/Fe(II)-dependent dioxygenases, we have tested a simple modeling strategy for the non-heme Fe(II) site in which the iron is represented by a simple +2 point charge with Lennard-Jones parameters. Calculations for an AlkB active site model in the gas phase and ∼150 ns molecular dynamics (MD) simulations for two enzyme-dsDNA complexes (E. coli AlkB-dsDNA and ABH2-dsDNA) suggest that this simple modeling strategy provides a satisfactory description of structural properties of the Fe(II) site in AlkB enzymes, provided that care is exercised to control the binding mode of carboxylate (Asp) to the iron. MD simulations using the model for AlkB-dsDNA and ABH2-dsDNA systems find that although the structural features for the latter are overall in good agreement with the crystal structure, the dsDNA, and AlkB-dsDNA interface undergo substantial changes during the MD simulations from the crystal structure. Even for ABH2, new interactions form between a long loop region and dsDNA upon structural relaxation of the loop, supporting the role of this loop in DNA binding despite the lack of interactions between them in the crystal structure. Analysis of DNA backbone torsional distributions helps identify regions that adopt strained conformations. Collectively, the results highlight that crystal packing may have a significant impact on the structure of protein-DNA complexes; the simulations also provide additional insights regarding why AlkB and ABH2 prefer single-strand and double-strand DNA, respectively, as substrate.
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Affiliation(s)
- Xueqin Pang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
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17
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Riccardi D, Zhu X, Goyal P, Yang S, Hou G, Cui Q. Toward molecular models of proton pumping: Challenges, methods and relevant applications. Sci China Chem 2011. [DOI: 10.1007/s11426-011-4458-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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18
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19
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Bedor CNG, Morais RJL, Cavalcanti LS, Ferreira JV, Pavão AC. Carcinogenic potential of endosulfan and its metabolites based on a quantum chemical model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:6281-6284. [PMID: 20889188 DOI: 10.1016/j.scitotenv.2010.09.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 09/03/2010] [Accepted: 09/09/2010] [Indexed: 05/29/2023]
Abstract
The aim of the present study was to investigate the carcinogenic potential of endosulfan and its metabolites through electronic parameters that characterize the action of carcinogens, i.e. descriptors such as electron affinity, Δ (HOMO-LUMO), dipole moments, electrostatic attraction, formation heat (H(f)) and permeability of the cell membrane (c Log P). The results reveal that both endosulfan and its metabolites are electrophilic and have carcinogenic potential. Although there are few data on its carcinogenicity in the literature, the findings of the present study indicate that the use of this pesticide represents a risk to the health of the general population, especially rural workers.
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Affiliation(s)
- C N G Bedor
- Universidade Federal do Vale do São Francisco, Av. José de Sá Maniçoba, S/N, Centro, 56304-205, Petrolina, PE, Brazil.
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“Multi-Scale” QM/MM Methods with Self-Consistent-Charge Density-Functional-Tight-Binding (SCC-DFTB). ACTA ACUST UNITED AC 2009. [DOI: 10.1007/978-1-4020-9956-4_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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21
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Araujo da Silva JC, Pillot JP, Birot M, Desvergne JP, Liotard D, Rayez JC, Rayez MT. The Si–B chromophore: A joint experimental and theoretical investigation. J Organomet Chem 2008. [DOI: 10.1016/j.jorganchem.2008.04.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Giese TJ, York DM. Charge-dependent model for many-body polarization, exchange, and dispersion interactions in hybrid quantum mechanical/molecular mechanical calculations. J Chem Phys 2008; 127:194101. [PMID: 18035873 DOI: 10.1063/1.2778428] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This work explores a new charge-dependent energy model consisting of van der Waals and polarization interactions between the quantum mechanical (QM) and molecular mechanical (MM) regions in a combined QMMM calculation. van der Waals interactions are commonly treated using empirical Lennard-Jones potentials, whose parameters are often chosen based on the QM atom type (e.g., based on hybridization or specific covalent bonding environment). This strategy for determination of QMMM nonbonding interactions becomes tedious to parametrize and lacks robust transferability. Problems occur in the study of chemical reactions where the "atom type" is a complex function of the reaction coordinate. This is particularly problematic for reactions, where atoms or localized functional groups undergo changes in charge state and hybridization. In the present work we propose a new model for nonelectrostatic nonbonded interactions in QMMM calculations that overcomes many of these problems. The model is based on a scaled overlap model for repulsive exchange and attractive dispersion interactions that is a function of atomic charge. The model is chemically significant since it properly correlates atomic size, softness, polarizability, and dispersion terms with minimal one-body parameters that are functions of the atomic charge. Tests of the model are examined for rare-gas interactions with neutral and charged atoms in order to demonstrate improved transferability. The present work provides a new framework for modeling QMMM interactions with improved accuracy and transferability.
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Affiliation(s)
- Timothy J Giese
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
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Yang Y, Yu H, York D, Cui Q, Elstner M. Extension of the Self-Consistent-Charge Density-Functional Tight-Binding Method: Third-Order Expansion of the Density Functional Theory Total Energy and Introduction of a Modified Effective Coulomb Interaction. J Phys Chem A 2007; 111:10861-73. [PMID: 17914769 DOI: 10.1021/jp074167r] [Citation(s) in RCA: 213] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The standard self-consistent-charge density-functional-tight-binding (SCC-DFTB) method (Phys. Rev. B 1998, 58, 7260) is derived by a second-order expansion of the density functional theory total energy expression, followed by an approximation of the charge density fluctuations by charge monopoles and an effective damped Coulomb interaction between the atomic net charges. The central assumptions behind this effective charge-charge interaction are the inverse relation of atomic size and chemical hardness and the use of a fixed chemical hardness parameter independent of the atomic charge state. While these approximations seem to be unproblematic for many covalently bound systems, they are quantitatively insufficient for hydrogen-bonding interactions and (anionic) molecules with localized net charges. Here, we present an extension of the SCC-DFTB method to incorporate third-order terms in the charge density fluctuations, leading to chemical hardness parameters that are dependent on the atomic charge state and a modification of the Coulomb scaling to improve the electrostatic treatment within the second-order terms. These modifications lead to a significant improvement in the description of hydrogen-bonding interactions and proton affinities of biologically relevant molecules.
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Affiliation(s)
- Yang Yang
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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Performance of the semiempirical AM1, PM3, MNDO, and tight-binding methods in comparison with DFT method for the large fullerenes C116–C120. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.theochem.2007.04.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Giese TJ, York DM. Improvement of semiempirical response properties with charge-dependent response density. J Chem Phys 2007; 123:164108. [PMID: 16268682 DOI: 10.1063/1.2080007] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The present work outlines a new method for treatment of charge-dependent polarizability in semiempirical quantum models for use in combined quantum-mechanical/molecular mechanical simulations of biological reactions. The method addresses a major shortcoming in the performance of conventional semiempirical models for these simulations that is tied to the use of a localized minimal atomic-orbital basis set. The present approach has the advantages that it uses a density basis that retains a set of linear-response equations, does not increase the atomic-orbital basis, and avoids the problem of artificial charge transfer and scaling of the polarizability seen in related models that allow atomic charges to fluctuate. The model introduces four new atom-based parameters and has been tested with the modified neglect of differential overlap d-orbital Hamiltonian against 1132 molecules and ions and shown to decrease the dipole moment and polarizability errors by factors of 2 and 10, respectively, with respect to density-functional results. The method performs impressively for a variety of charge states (from 2+ to 2-), and offers a potentially powerful extension in the design of next generation semiempirical quantum models for accurate simulations of highly charged biological reactions.
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Affiliation(s)
- Timothy J Giese
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Langhoff PW, Boatz JA, Hinde RJ, Sheehy JA. Atomic spectral methods for molecular electronic structure calculations. J Chem Phys 2004; 121:9323-42. [PMID: 15538852 DOI: 10.1063/1.1794634] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Theoretical methods are reported for ab initio calculations of the adiabatic (Born-Oppenheimer) electronic wave functions and potential energy surfaces of molecules and other atomic aggregates. An outer product of complete sets of atomic eigenstates familiar from perturbation-theoretical treatments of long-range interactions is employed as a representational basis without prior enforcement of aggregate wave function antisymmetry. The nature and attributes of this atomic spectral-product basis are indicated, completeness proofs for representation of antisymmetric states provided, convergence of Schrodinger eigenstates in the basis established, and strategies for computational implemention of the theory described. A diabaticlike Hamiltonian matrix representative is obtained, which is additive in atomic-energy and pairwise-atomic interaction-energy matrices, providing a basis for molecular calculations in terms of the (Coulombic) interactions of the atomic constituents. The spectral-product basis is shown to contain the totally antisymmetric irreducible representation of the symmetric group of aggregate electron coordinate permutations once and only once, but to also span other (non-Pauli) symmetric group representations known to contain unphysical discrete states and associated continua in which the physically significant Schrodinger eigenstates are generally embedded. These unphysical representations are avoided by isolating the physical block of the Hamiltonian matrix with a unitary transformation obtained from the metric matrix of the explicitly antisymmetrized spectral-product basis. A formal proof of convergence is given in the limit of spectral closure to wave functions and energy surfaces obtained employing conventional prior antisymmetrization, but determined without repeated calculations of Hamiltonian matrix elements as integrals over explicitly antisymmetric aggregate basis states. Computational implementations of the theory employ efficient recursive methods which avoid explicit construction the metric matrix and do not require storage of the full Hamiltonian matrix to isolate the antisymmetric subspace of the spectral-product representation. Calculations of the lowest-lying singlet and triplet electronic states of the covalent electron pair bond (H(2)) illustrate the various theorems devised and demonstrate the degree of convergence achieved to values obtained employing conventional prior antisymmetrization. Concluding remarks place the atomic spectral-product development in the context of currently employed approaches for ab initio construction of adiabatic electronic eigenfunctions and potential energy surfaces, provide comparisons with earlier related approaches, and indicate prospects for more general applications of the method.
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Affiliation(s)
- P W Langhoff
- San Diego Supercomputer Center, University of California, La Jolla, California 92093-0505, USA.
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Pichierri F. Substitution effects on the frontier orbitals of 3,4,9,10-perylene bis(dicarboximide). A computational quantum chemistry study with insights into the electronic properties of organic semiconductors. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.theochem.2004.08.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Khandogin J, York DM. Quantum descriptors for biological macromolecules from linear-scaling electronic structure methods. Proteins 2004; 56:724-37. [PMID: 15281126 DOI: 10.1002/prot.20171] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The characterization of electrostatic and chemical properties at the surface of biological macromolecules is of interest in elucidating the fundamental biological structure-function relationships as well as in problems of rational drug design. This paper presents a set of macromolecular quantum descriptors for the characterization of biological macromolecules in solution that can be obtained with modest computational cost from linear-scaling semi-empirical quantum/solvation methods. The descriptors discussed include: solvent-polarized electrostatic surface potential maps, equilibrated atomic charges, Fukui reactivity indices, approximate local hardness maps, and relative proton potentials. These properties are applied to study the conformational dependence of the electrostatic surface potential of the solvated phosphate-binding protein mutant (T141D), the regioselectivity of the zinc finger domains of HIV-1 nucleocapsid (NC) protein, and the order of pKa values of acidic residues in turkey ovomucoid third domain (OMTKY3) and of the zinc-binding residues in the carboxyl terminal zinc finger of NC. In all cases, insight beyond that obtainable from purely classical models is gained and can be used to rationalize the experimental observations. The macromolecular quantum descriptors presented here greatly extend the arsenal of tools for macromolecular characterization and offer promise in applications to modern structure-based drug design.
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Affiliation(s)
- Jana Khandogin
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Pichierri F. A quantum mechanical study on phosphotyrosyl peptide binding to the SH2 domain of p56lck tyrosine kinase with insights into the biochemistry of intracellular signal transduction events. Biophys Chem 2004; 109:295-304. [PMID: 15110947 DOI: 10.1016/j.bpc.2003.12.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2003] [Revised: 12/05/2003] [Accepted: 12/05/2003] [Indexed: 11/20/2022]
Abstract
A study on the interaction between a phosphotyrosyl peptide with the SH2 domain of Lck kinase has been undertaken with the aid of semiempirical linear-scaling quantum mechanical methods. The structure of this complex has been solved at atomic resolution and, hence, it represents the ideal candidate for studying the charge deformation effects induced by the phosphopeptide on the binding site. Substantial changes in the charge of amino acid residues located in the binding pocket of the protein are observed upon ligand binding. More specifically, our quantum chemical calculations indicate that H-bonds involving charged side-chains are subject to consistent charge deformation effects whereas those forming salt bridges are unaffected by ligand binding. Furthermore, ligand binding has the effect of changing both the magnitude and direction of the protein's macrodipole, which rotates approximately 150 degrees with respect that of the unliganded protein. This suggests that a change in the polarization state of the protein might acts as a switch during the transmission of intracellular signals. The binding energy calculated with the aid of the COSMO solvation model corresponds to about -200 kcal/mol, most of which is attributed to the interaction of the phosphotyrosine head with the amino acid chains located in the binding site of the SH2 domain.
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Affiliation(s)
- Fabio Pichierri
- COE Laboratory, IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
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Pichierri F. Computation of the permanent dipole moment of α-chymotrypsin from linear-scaling semiempirical quantum mechanical methods. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/j.theochem.2003.09.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Giese TJ, Audette VM, York DM. Examination of the correlation energy and second virial coefficients from accurateab initiocalculations of rare-gas dimers. J Chem Phys 2003. [DOI: 10.1063/1.1587684] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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Hirokawa S, Imasaka T, Urakami Y. Ab initio MO study on the S1←S0 transitions of polychlorinated dibenzo-p-dioxins. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0166-1280(02)00648-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cossi M, Barone V. Time-dependent density functional theory for molecules in liquid solutions. J Chem Phys 2001. [DOI: 10.1063/1.1394921] [Citation(s) in RCA: 1683] [Impact Index Per Article: 73.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Efremenko I. Implication of palladium geometric and electronic structures to hydrogen activation on bulk surfaces and clusters. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s1381-1169(01)00144-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Ruette F, Gonzalez C, Octavio A. Fundamental properties of parametric functionals in quantum chemistry. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0166-1280(00)00659-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Johnson MR, Kearley GJ. Quantitative atom-atom potentials from rotational tunneling: their extraction and their use. Annu Rev Phys Chem 2000; 51:297-321. [PMID: 11031284 DOI: 10.1146/annurev.physchem.51.1.297] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Rotational tunneling of small molecular groups has been the subject of considerable theoretical and experimental activity for several decades. Much of this activity has been driven by the promise of exploiting the extreme sensitivity of quantum tunneling to interatomic potentials, but until recently, there was no straightforward means by which quantitative information about these potentials could be extracted. This review explains how a quantitative method, suitable for general application, was developed. It then goes on to show how this has been used to understand tunneling systems for which no previous satisfactory explanation had been found. The application of the methodology, and its results, to other disciplines is discussed.
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Affiliation(s)
- M R Johnson
- Institut Laue Langevin, BP 156, 38042 Grenoble, Cedex 09, France.
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Johnson M, Prager M, Grimm H, Neumann M, Kearley G, Wilson C. Methyl group dynamics in paracetamol and acetanilide: probing the static properties of intermolecular hydrogen bonds formed by peptide groups. Chem Phys 1999. [DOI: 10.1016/s0301-0104(99)00138-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Prezhdo V, Vaschenko E, Prezhdo O, Puszko A. Molecular structure and electric properties of some pyridine and pyridine-N-oxide derivatives. J Mol Struct 1998. [DOI: 10.1016/s0022-2860(98)00396-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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