1
|
Davtyan A, Dama JF, Sinitskiy AV, Voth GA. The Theory of Ultra-Coarse-Graining. 2. Numerical Implementation. J Chem Theory Comput 2014; 10:5265-75. [PMID: 26583210 DOI: 10.1021/ct500834t] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The increasing interest in the modeling of complex macromolecular systems in recent years has spurred the development of numerous coarse-graining (CG) techniques. However, many of the CG models are constructed assuming that all details beneath the resolution of CG degrees of freedom are fast and average out, which sets limits on the resolution of feasible coarse-grainings and on the range of applications of the CG models. Ultra-coarse-graining (UCG) makes it possible to construct models at any desired resolution while accounting for discrete conformational or chemical changes within the CG sites that can modulate the interactions between them. Here, we discuss the UCG methodology and its numerical implementation. We pay particular attention to the numerical mechanism for including state transitions between different conformations within CG sites because this has not been discussed previously. Using a simple example of 1,2-dichloroethane, we demonstrate the ability of the UCG model to reproduce the multiconfigurational behavior of this molecular liquid, even when each molecule is modeled with only one CG site. The methodology can also be applied to other molecular liquids and macromolecular systems with time scale separation between conformational transitions and other intramolecular motions and rotations.
Collapse
Affiliation(s)
- Aram Davtyan
- Department of Chemistry, The James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States
| | - James F Dama
- Department of Chemistry, The James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States
| | - Anton V Sinitskiy
- Department of Chemistry, The James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States
| | - Gregory A Voth
- Department of Chemistry, The James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States
| |
Collapse
|
2
|
Dama JF, Sinitskiy AV, McCullagh M, Weare J, Roux B, Dinner AR, Voth GA. The Theory of Ultra-Coarse-Graining. 1. General Principles. J Chem Theory Comput 2013; 9:2466-80. [PMID: 26583735 DOI: 10.1021/ct4000444] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Coarse-grained (CG) models provide a computationally efficient means to study biomolecular and other soft matter processes involving large numbers of atoms correlated over distance scales of many covalent bond lengths and long time scales. Variational methods based on information from simulations of finer-grained (e.g., all-atom) models, for example the multiscale coarse-graining (MS-CG) and relative entropy minimization methods, provide attractive tools for the systematic development of CG models. However, these methods have important drawbacks when used in the "ultra-coarse-grained" (UCG) regime, e.g., at a resolution level coarser or much coarser than one amino acid residue per effective CG particle in proteins. This is due to the possible existence of multiple metastable states "within" the CG sites for a given UCG model configuration. In this work, systematic variational UCG methods are presented that are specifically designed to CG entire protein domains and subdomains into single effective CG particles. This is accomplished by augmenting existing effective particle CG schemes to allow for discrete state transitions and configuration-dependent resolution. Additionally, certain conclusions of this work connect back to single-state force matching and open up new avenues for method development in that area. These results provide a formal statistical mechanical basis for UCG methods related to force matching and relative entropy CG methods and suggest practical algorithms for constructing optimal approximate UCG models from fine-grained simulation data.
Collapse
Affiliation(s)
- James F Dama
- Department of Chemistry and Institute for Biophysical Dynamics, ‡Computation Institute, §James Franck Institute, ∥Department of Mathematics, ⊥Department of Biochemistry and Molecular Biology, University of Chicago , Chicago, Illinois 60637, United States
| | - Anton V Sinitskiy
- Department of Chemistry and Institute for Biophysical Dynamics, ‡Computation Institute, §James Franck Institute, ∥Department of Mathematics, ⊥Department of Biochemistry and Molecular Biology, University of Chicago , Chicago, Illinois 60637, United States
| | - Martin McCullagh
- Department of Chemistry and Institute for Biophysical Dynamics, ‡Computation Institute, §James Franck Institute, ∥Department of Mathematics, ⊥Department of Biochemistry and Molecular Biology, University of Chicago , Chicago, Illinois 60637, United States
| | - Jonathan Weare
- Department of Chemistry and Institute for Biophysical Dynamics, ‡Computation Institute, §James Franck Institute, ∥Department of Mathematics, ⊥Department of Biochemistry and Molecular Biology, University of Chicago , Chicago, Illinois 60637, United States
| | - Benoît Roux
- Department of Chemistry and Institute for Biophysical Dynamics, ‡Computation Institute, §James Franck Institute, ∥Department of Mathematics, ⊥Department of Biochemistry and Molecular Biology, University of Chicago , Chicago, Illinois 60637, United States
| | - Aaron R Dinner
- Department of Chemistry and Institute for Biophysical Dynamics, ‡Computation Institute, §James Franck Institute, ∥Department of Mathematics, ⊥Department of Biochemistry and Molecular Biology, University of Chicago , Chicago, Illinois 60637, United States
| | - Gregory A Voth
- Department of Chemistry and Institute for Biophysical Dynamics, ‡Computation Institute, §James Franck Institute, ∥Department of Mathematics, ⊥Department of Biochemistry and Molecular Biology, University of Chicago , Chicago, Illinois 60637, United States
| |
Collapse
|