Molecular dynamics (MD) is an extremely powerful, highly effective, and widely used approach to understanding the nature of chemical processes in atomic details for proteins. The accuracy of results from MD simulations is highly dependent on force fields. Currently, molecular mechanical (MM) force fields are mainly utilized in MD simulations because of their low computational cost. Quantum mechanical (QM) calculation has high accuracy, but it is exceedingly time consuming for protein simulations. Machine learning (ML) provides the capability for generating accurate potential at the QM level without increasing much computational effort for specific systems that can be studied at the QM level. However, the construction of general machine learned force fields, needed for broad applications and large and complex systems, is still challenging. Here, general and transferable neural network (NN) force fields based on CHARMM force fields, named CHARMM-NN, are constructed for proteins by training NN models on 27 fragments partitioned from the residue-based systematic molecular fragmentation (rSMF) method. The NN for each fragment is based on atom types and uses new input features that are similar to MM inputs, including bonds, angles, dihedrals, and non-bonded terms, which enhance the compatibility of CHARMM-NN to MM MD and enable the implementation of CHARMM-NN force fields in different MD programs. While the main part of the energy of the protein is based on rSMF and NN, the nonbonded interactions between the fragments and with water are taken from the CHARMM force field through mechanical embedding. The validations of the method for dipeptides on geometric data, relative potential energies, and structural reorganization energies demonstrate that the CHARMM-NN local minima on the potential energy surface are very accurate approximations to QM, showing the success of CHARMM-NN for bonded interactions. However, the MD simulations on peptides and proteins indicate that more accurate methods to represent protein–water interactions in fragments and non-bonded interactions between fragments should be considered in the future improvement of CHARMM-NN, which can increase the accuracy of approximation beyond the current mechanical embedding QM/MM level.
Skip Nav Destination
Article navigation
14 July 2023
Research Article|
July 11 2023
Toward a general neural network force field for protein simulations: Refining the intramolecular interaction in protein
Special Collection:
Machine Learning Hits Molecular Simulations
Pan Zhang
;
Pan Zhang
(Data curation, Formal analysis, Investigation, Software, Validation, Visualization, Writing – original draft)
Department of Chemistry, Duke University
, Durham, North Carolina 27708, USA
Search for other works by this author on:
Weitao Yang
Weitao Yang
a)
(Conceptualization, Funding acquisition, Methodology, Project administration, Resources, Supervision, Writing – review & editing)
Department of Chemistry, Duke University
, Durham, North Carolina 27708, USA
a)Author to whom correspondence should be addressed: weitao.yang@duke.edu
Search for other works by this author on:
a)Author to whom correspondence should be addressed: weitao.yang@duke.edu
J. Chem. Phys. 159, 024118 (2023)
Article history
Received:
January 12 2023
Accepted:
June 22 2023
Citation
Pan Zhang, Weitao Yang; Toward a general neural network force field for protein simulations: Refining the intramolecular interaction in protein. J. Chem. Phys. 14 July 2023; 159 (2): 024118. https://doi.org/10.1063/5.0142280
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Sign in via your Institution
Sign in via your InstitutionPay-Per-View Access
$40.00